Police in Nepal announced on Friday that the arrest of two men who were allegedly involved in the 2012 disappearance of Aubrey Sacco, a 23-year-old University of Colorado graduate.

Sacco, who hailed from Greeley, Colo., went missing in 2010 during a solo hike in Nepal’s Langtang region, The Associated Press reports. The 23-year-old went hiking near the end of “trekking season,” a time when few others travel in the area.

The two suspects allegedly involved in Sacco’s disappearance were arrested Thursday in Rasuwa, Nepal, not far from where she went originally went missing, AP reports. The suspects, who have yet to be officially named, were being questioned by Nepali police, spokesperson Raj Kumar Shrestha said. These are the first arrested that have been made during the Sacco investigation.

In an interview with Boulder, Colo., newspaper The Daily Camera, Sacco’s father revealed that the family had learned of the arrests through the media, and had yet to receive confirmation from officials. “We’re kind of in shock,” Paul Sacco told The Daily Camera on Friday. “We have some very good people working on this case, and when they tell me this then I’ll believe it. We’ve learned to be very cautious about these reports.

A seasoned traveler, Sacco had been living in Nepal for over five months at the time of her disappearance, and spent her time teaching yoga and sightseeing, The Daily Camera reports. Her parents became aware that she was missing after she failed to contact them for several days after she was scheduled to return home.

The Sacco family, including Paul, his wife Connie, and sons Crofton and Morgan, has made several trips to Nepal to search for their missing daughter, The Daily Camera reports. They managed to recover her laptop and various personal effects from her hotel room in 2011, but a partnership with Nepalese military and police officials had yet to yield much evidence—until now.

“In a way we feel…I don’t know. Horror and sadness and vindication at the same time that our people have worked for us so hard and so well that we may actually have answers,” Sacco said after the suspects were arrested. “It’s both relief and horrible news because it means that perhaps she’s not out there and alive somewhere.”