A helicopter with 22 people aboard, most of them tourists, has gone missing in Russia's Kamchatka peninsula in the far east, regional authorities said Saturday."Today at about 16:15 [0415 GMT] communication was lost with a Mi-8 helicopter...which had 22 people on board, 19 passengers and three crew members," Kamchatka Governor Vladimir Solodov said in a video posted on Telegram.Rescue teams in helicopters have been searching into the night for the missing aircraft, focusing on a river valley that the helicopter was due to fly along, Russian authorities said.The Mi-8 is a Soviet-designed military helicopter that is widely used for transport in Russia.The missing helicopter had picked up passengers near the Vachkazhets ancient volcano in a scenic area of the peninsula known for its wild landscapes and active volcanoes.A source in the emergency services told TASS news agency that the helicopter disappeared from radar almost immediately after taking off and the crew did not report any problems.The local weather service said that there was poor visibility in the area of the airport.Accidents involving planes and helicopters are very frequent in Russia's far eastern region, which is sparsely populated and where there is often harsh weather.In August 2021, a Mi-8 helicopter with 16 people on board including 13 tourists crashed into a lake in Kamchatka due to poor visibility, killing eight.In July the same year, a plane crashed as it came in to land on the peninsula, with 22 passengers and 6 crew aboard, all of whom were killed.