Murder investigation opened into disappearance of US citizen Colin Madsen in Siberia

No trace has been found of Madsen, who was studying at an Irkutsk university, after he vanished from a guest house in Arshan, Buryatia at around 3am on Sunday. 

While there is no hard evidence that he was killed, a murder probe has been opened, said statement from the Investigative Committee - seen as equivalent of the FBI - in the Republic of Buryatia. 

'During the preliminary check, we have not confirmed that the missing young man was about to leave the resort village and his friends,' said the statement. 'These and other established facts indicate that a crime may have been committed against him. 

'Therefore, Tunkinsky Interdistrict Investigation Department of the Investigative Committee in the Republic of Buryatia opened a criminal case on the grounds of a crime under Part. 1, Art. 105 of the Criminal Code (Murder).'

Three friends with whom Madsen was travelling are understood to have been questioned. Local TV channel Arig-Us reported the 'first suspects' were his friends - understood to include one American - but the actual status of the questioning has not been disclosed. 

The guest house was also checked for traces of blood. Madsen's friend Vlad Rasputin, 20, said: 'They came yesterday, and checked the biological traces. But the forensics have no grounds, they have not found anything... They are interrogating all us with a polygraph.'

Madsen's mother Dana arrived in Buryatia today and is now in Arshan village with the investigators. The Emergencies' Ministry (EMERCOM) is using drones to search the area around Arshan, which includes the Peak of Love, a mountain that Madsen and his friends had been due to start climbing two hours after he disappeared. 

'We plan to involve additional equipment - Phantom-3 unmanned aerial vehicles. With their help will be checked the forest, ravines, the bed of the Kyngarga River and other places which are hard to reach.'

Searches in recent days have found no trace of Madsen. Search and rescue team 'Volunteer-Angarsk' is gathering money for the operation to find the missing American. It is working in collaboration with the police and EMERCOM.

Money is being spent on printing fliers, as well as travel and road expenses to Arshan for volunteers. They posted in English: 'Please, donate to help organize the search for Colin Madsen who has been missing since March 27 from Arshan.' 

Banking details for donations:

PayPal: http://paypal.me/volonter

Yandex.Money: 41001152788189 (Sberbank online, no transaction fee at https://money.yandex.ru/doc.xml?id=523854), see https://money.yandex.ru/prepaid/ for other ways of donation.

MasterCard: 5106 2140 0075 9729 (paid to Zavyalov Dmitry Vladimirovich

Money transaction using VISA or MasterCard

Friends of Madsen, from Jefferson City, Missouri, say he was known to venture out at night in Irkutsk, where he studied at a linguistics university. But when he disappeared he did not take his cellphone or his coat despite subzero temperatures. The group had agreed to rise at 5am to climb the 2412-metre high Peak of Love (7,913 feet), a mysterious mountain in the Eastern Sayan range. 

Even local shamans - who blame tourists for getting into trouble because they do not respect ancient traditions and honour 'sacred' sites - are helping with the search. Buryatia is a Buddhist region in southern Siberia.