JEFFERSON CITY, Missouri (CBS NEWS) -- The search for an American college student who disappeared in Siberia ended tragically after Russian officials announced they had discovered his body.

CBS affiliate KRCG in Jefferson City reports the body of Colin Madsen was found a little more than a mile from Arshan village, where he was staying before his disappearance.

On Friday, the Siberian Times reported that the Investigative Committee - seen as equivalent of the FBI - had opened a murder investigation in the Republic of Buryatia, although it is unclear whether that was still ongoing after Madsen's body was found.

Annie Madsen of Markle, Indiana, said that her nephew apparently left the house without a coat in below-freezing temperatures while others in the guest house slept. He disappeared a day after he arrived with another American as part of a group from Irkutsk, where he was a university student. She said her nephew is fluent in Russian and has taught English in Russia.

Photos of Madsen were widely distributed across Russian social media sites and major newspapers, and were shown Thursday on several leading TV channels.

In addition to the police, members of national volunteer search and rescue teams and staff of the national park in Buryatia were involved in the search operation, which took place in a forest in the foothills of the Sayan Mountains.