Now Four Years Gone, Family Fears Worst For Missing Gillette Student Irene Gakwa

GILLETTE — It’s been four years since Irene Gakwa vanished from the Gillette home she shared with Nathan Hightman, her boyfriend at the time.

In the years since her disappearance, there have been no confirmed sightings of Gakwa nor has she reached out to family or friends or left any digital footprint online.

Hightman remains a person of interest in her disappearance, and newly released court documents provide insight into his actions in the days and weeks following Gakwa’s last sighting in Gillette.

It’s this behavior that police say “indicates a pattern of suspicious behavior,” according to Brent Wasson, interim chief of the Gillette Police Department, that landed Hightman on their radar.

Thus far, Hightman, now 42, maintains his innocence, though Gakwa’s family feel that he knows much more than he is letting on.

Though not charged in relation to her disappearance, Hightman’s actions following Gakwa’s departure landed him in prison after he drained her bank account and maxed out her credit card for just under $7,000, as well as deleted her email account.

Initially, he faced five felony charges, but ultimately pleaded guilty to three for theft, unlawful use of a credit card and intellectual property crimes as part of a plea deal. 

His excuse to police was that he was holding her money hostage to force her to contact him.

In Prison

Hightman was sentenced to three to six years in prison on June 14, 2023, was granted parole on Oct. 8, 2024 and released in spring 2025. 

He’s now on parole and living in Cheyenne with a discharge date of Feb. 11, 2031, according to the Wyoming Department of Corrections. 

Cowboy State Daily was unable to locate Hightman for comment, but in the past, he has denied any culpability in Gakwa’s disappearance and insists she left on her own accord.

Meanwhile, the investigation is ongoing as a new detective takes lead on the case and her family deals with the uncertainty and pain as they mark the fourth year since she’s been gone. 

They’re optimistic that one day they may finally learn the truth about what happened.

“It would mean the world to us to finally have closure, so we can start healing,” said Gakwa’s oldest brother, Kennedy Wainaina. “Every day we beg to get justice for her.”

Local police also want that justice and say they believe the case is still solvable.

“The investigation into Irene’s disappearance is very active,” Wasson said. “We truly want to give the family answers and believe it’s possible.”

Grim Reminder

In the meantime, Gakwa’s family once again marked the grim anniversary with a visit to a Chinese buffet, Gakwa’s favorite. 

When she initially moved from Nairobi, Kenya, to Idaho in 2019, the hardest part was adjusting to American food, Wainaina said.

All three children immigrated to the United States to attend college and build careers. 

Wainaina and his younger brother, Christopher Gakwa, moved to the Boise area after high school. Wainaina is now a pharmacist while his brother is a psychiatric nurse practitioner. 

Both married and have families in the tight-knit Kenyan community in their adopted country.

Gakwa also came to Idaho at age 29 to attend nursing school and be closer to her brothers and family. That’s where she met Hightman on Craigslist, and the two dated for about 18 months before moving to Wyoming.

Wainaina described his sister as quiet and very loving and loyal. 

At around 5 feet tall and weighing less than 100 pounds, she was also very petite and not much of an eater. 

Wainaina said he would tease her to try other things at the Chinese buffet beyond her favorite fried rice, egg rolls and a chicken dish, but she knew what she liked.

His sister loved helping people and was excited about nursing school.

She was also secretive about Hightman, who the family never took to and had no idea that the couple had moved to Gillette. As far as they knew, they’d broken up and Irene had moved to Arizona with a female friend to escape Idaho’s harsh winters.

They believe now that Hightman had purposely isolated Gakwa from her friends and family as a means of coercive control.

They wished they’d known, Wainaina said, but at the same time, they wanted to give their little sister a sense of independence as she forged her new life in America.

Messages Stopped

The family grew concerned when Gakwa, then 32, stopped communicating with them and stopped posting on her social media accounts in late February 2022.

Gakwa was very close with family, particularly her parents in Kenya to whom she spoke at least once a day whether through video call or text messages.

She was last spotted on a video call with her parents on Feb. 24. Following that date, she communicated only through messages, suddenly making excuses for why she couldn’t appear on video.

Her text messages at that point also took on a different tone, the family says. Usually, she communicated in a mix of her native Swahili and English, but thereafter she wrote only in English.

These stopped altogether on March 9, 2022, at which point the family worriedly attempted to find her. 

After that, her phone went straight to voicemail and posts on her Facebook page also stopped before the account was deactivated altogether.

She was reported missing by her brothers on March 20, 2022.

What Hightman Says

When questioned by Gillette police after Gakwa was reported missing, Hightman said she’d willingly left on her own one night in late February.

He said she returned from dinner on her own, telling him she was unhappy in the relationship and was moving out, Hightman told police.

He then said Gakwa packed her belongings into two plastic trash bags and drove off with a guy she’d met online, potentially named “Marco,” in a dark-colored SUV he didn’t recognize.

She also abruptly quit her job over text message and stopped attending classes at Gillette College. 

Her last appearance on campus was Feb. 23, 2022. 

When she failed to show up for class two days later, her classmates grew worried, according to recently released court documents from Hightman’s closed theft case.

Strange Messages

One of those classmates texted with Gakwa between Feb. 25 and March 10, during which she expressed her concern for Irene, court documents state.

One message she received from Irene’s phone number said that Gakwa had abruptly moved to San Antonio, Texas, and provided the friend with an address and photo of her new home.

When police checked the address, however, they found it was a new construction home that had just sold for over $600,000.

The owners had never heard of Gakwa, court documents state, and when police reverse searched the photo of the home, it was determined to be a bed and breakfast in Wisconsin.

After looking into the new address in Texas, investigators learned that the change of address was initiated on March 1 from a computer with an IP address matching Hightman’s.

Another classmate close to Gakwa grew concerned that she might be being sex trafficked and contacted the FBI human trafficking hotline. 

Much like Gakwa’s family, the friend thought the messages didn’t sound like Gakwa, so she asked about a party the two had recently attended to which the person messaging was unable to answer, say court documents.

This same friend later told police that on March 20, shortly after being questioned by police, Hightman showed up unexpectedly at her apartment to ask about Gakwa. 

Prior to this visit, the two had never met or spoken, and she questioned how he knew where she lived.

Information Not Adding Up

Other behaviors also struck police as suspicious as indicated in a search and seizure affidavit filed by police.

After obtaining a search warrant, investigators discovered Gakwa’s phone last pinged a cell tower on Garner Lake Road on March 7, about two weeks after Hightman reported she’d left town.

Garner Lake Road is a route that runs from Gillette north until it intersects with Highway 59 near the Rawhide coal mine.

Meanwhile, her last location captured by Google was on Feb. 25 about 98 feet east of the couple’s residence, which coincided with her last log in to her Gmail account, court documents state.

This account continued to be accessed up until March 15, 2022, from an IP address registered to the internet service at Hightman’s house. 

More Red Flags

Likewise, Hightman himself was reportedly acting out of character, police learned after interviewing neighbors.

Typically, Hightman was described by neighbors as a “homebody,” they told police. They reported rarely seeing him outside and that he frequently had his meals and groceries delivered.

They also told police he didn’t socialize with the neighbors nor was he seen outside doing physical or yard activities, court documents state.  

His behavior changed following Gakwa’s disappearance, however, with one neighbor reporting seeing Hightman burning something in his backyard, police say.

Hightman also became much more social following his initial interview with police on March 20, at which point he began talking to his neighbors, court documents indicate, asking them about Gakwa and where she might have gone.

Police found this line of questioning increasingly suspicious, noting that it was Hightman himself who reported Gakwa leaving in the vehicle in late February.

“Based on his statement, he knew what happened to Irene,” wrote GPD Detective Julianne Witham in a May 17, 2022, search and seizure affidavit.

Suspicious Purchases

Several of his purchases using Gakwa’s bank card, as well as his phone calls in the days following Gakwa’s disappearance, also caught the attention of investigators.

Along with transferring money from Gakwa’s account into his, Hightman was spotted at Walmart buying waterproof work boots, work pants and a shovel on Feb. 25, 2025.

These items were later located in his home. 

The shovel was found in his garage with “grime and possibly burnt material” on the blade with a dark colored, oily substance on the handle, according to court documents.

The boots were also located in Hightman’s dining room, though Hightman told police he’d thrown the pants away.

Wasson said that these items — along with others seized in a nearly eight-hour search of Hightman’s home with an FBI forensic team on  October 2022 — were sent to the FBI lab in Quantico, Virginia.

Hightman’s gray-colored Subaru was also searched, during which investigators noted that the back seat was laid down and there were dirt smudges on the back of the front seats and in the back area of the vehicle, according to court documents.

Additionally, investigators noted “dirty handprints on the steering wheel and parking brake.”

Also, on Feb. 25, 2022, Hightman made a series of phone calls to area farm and ranch supply stores — Menards, Bomgaars and Thars Farm and Ranch Supply Store — as well as Stotz Equipment rentals in Casper.

He also called Homax Oil and Heritage Health Care as well as a handful of friends that Wasson said have all been interviewed by police.

Unusual Movement 

Along with these phone calls and purchases, investigators also noted a marked change in Hightman’s physical behavior in the two weeks after Gakwa was said to have disappeared, based on the location data from his phone, according to an affidavit filed in his case.

There were several gaps in activity in which Hightman’s phone or location data appeared to be turned off, though the location information available showed a significant change in behavior for the typically homebound man.

During this period, Hightman appeared to have driven all around town with numerous pings hitting “all around McManaman Park,” a city park located about 2 miles from his home. 

Location data further indicated he’d also traveled to “multiple rural and industrial areas, numerous businesses in town and several ping well outside of the city in remote areas,” says the affidavit.

This activity corresponds with an early release in May 2022 from the Gillette Police Department in which they asked residents to report any sightings of a silver/gray Subaru Crosstrek, the vehicle Hightman drove, as well as a 55-gallon barrel in rural or industrial areas between the dates of Feb. 24 and March 20.

Gillette police are still looking for that barrel, Wasson confirmed, and are still asking anyone with information or video surveillance from that timeframe to contact their office.

“We are still very much welcoming any information that someone may have,” he said. 

The police have also conducted their own searches of these areas based on cellphone information, Wasson said, and will continue to conduct searches as new information becomes available.

Mostly Silent

To date, Hightman has not been charged with any crimes directly related to Gakwa’s disappearance and maintains his innocence, but has remained a person of interest with authorities.

As a result of his imprisonment, he has since lost his home to foreclosure, real-estate records show. 

In a 2024 letter to this reporter written from the Wyoming State Penitentiary during his incarceration, Hightman said he was being kept in isolation for his safety, though he wished to be housed in general population so he could work.

He did not discuss Gakwa, but did lament his imprisonment and losing his home and all of his possessions, which he described as “the worst thing ever, like watching a train wreck, being tied down, unable to stop it,” he said. 

Following the letter, Hightman has not responded to any additional correspondence offering him the opportunity to share his side of the story.

Some Kind of Closure

Gakwa’s family firmly believes that evidence suggests Hightman is responsible for her disappearance, Wainaina said, or at very least knows much more than he’s letting on.

It’s a particularly hard pill to swallow, Wainaina said, given that they once had invited Hightman into their homes as a guest and trusted him not to harm her.

Wainaina said he and his family have little hope that Gakwa is still alive. At this point, all they can ask for is to one day get answers so they, too, can begin to heal.

They’re also asking for accountability.

“And if he [Hightman] did something to my sister, I want to make sure he takes responsibility, you know,” Wainaina said. “First, we want to find out what happened, so we can get some closure and then we also want some action taken and charges brought.”

They don’t need the details, he noted; all of this has been hard enough.

He also said he wished he would have done more to push for answers and asks police to continue their efforts to investigate his sister’s disappearance.

So far, he’s spoken to the new detective on Gakwa’s case a handful of times and is hopeful that fresh eyes on existing evidence will make a difference.

“I would really like for them to put in the time and do the best they can for Irene,” he said. “I wish they’d think of it like their own sister or daughter.”

Four years later, the Gillette community continues to rally around Gakwa to seek justice and answers into what happened to her, including conducting dozens of searches of their own throughout the county.

These efforts have been led by Gillette resident and founder of the local missing person non-profit, WyoFind, Stacy Koester, who has formed a tight connection with her family and has vowed to continue searching.  

This also includes hanging posters throughout town, and most recently, on billboards in Cheyenne donated by Lamar Advertising.

“Hundreds of hours have been spent in volunteer searches, alongside the dedicated efforts of law enforcement working to bring her family answers,” Koester said. “We will continue to fight for justice for Irene and her family.”

Anyone with information is asked to contact the Gillette Police Department at 307-682-5155 or the Wyoming Division of Criminal Investigation at 307-777-7181. Tips can also be submitted anonymously on DCI’s website. 

Contact Jen Kocher at jen@cowboystatedaily.com

Jen Kocher can be reached at jen@cowboystatedaily.com.