Nine people fell in a car under the ice of Lake Baikal and eight of them died, TASS reported.
The tragedy occurred at around 3:30 p.m. local time on February 20 near Cape Khoboy.
The tourists were traveling in a UAZ car. The Russian Emergencies Ministry reported that two vehicles and five rescuers from the Baikal search and rescue team were sent to the scene of the incident.
The identities of the deceased have been established. Among them is a child.
The group of tourists and the driver disappeared in a car that sank in Lake Baikal, the Irkutsk Region Prosecutor's Office told TASS.
One of them was rescued, and the whereabouts of the other passengers and the driver are being established.
The circumstances and causes of the incident are being investigated.
The ice crossing to Olkhon Island on Lake Baikal is closed, and access to the ice is prohibited.
A case has been opened under Art. 238, Art. 3 of the Criminal Code of Russia (provision of services that do not meet safety requirements, which led to the death of two or more persons through negligence), Art. 293, Art. 3 of the Criminal Code of Russia (negligence).
The Chinese Consulate in Irkutsk has been notified of the incident.
According to Governor Igor Kobzev, four of the eight tourists, according to preliminary information, arrived on the excursion from China independently.
It is not yet clear whether the remaining tourists were officially registered.
The driver of the car was a local resident born in 1981, law enforcement officials told TASS.
In his youth, he had a criminal record for robbery.
The tourists did not book the excursion through tour operators, but organized the trip directly with a local resident, the Association of Tour Operators of Russia reported.
The Investigative Committee reported that the survivor was questioned and is in satisfactory condition.