The An-26 aircraft may have crashed into the sea near the Kamchatka peninsula or hit the ground near a village, several Russian agencies reported on Tuesday, citing sources in the security agencies.
Earlier, the Russian Civil Defence had confirmed that the radio contact with the pilots had been lost.
The plane was reportedly on its way from the region’s capital, Petropavlovsk-Kamchatsky, to the town of Palana.
The aircraft may have crashed 10 kilometres outside Palana, according to local media, citing the authorities.
The Russian Federal Agency for Air Transport (Rosaviatsiya) said conditions were foggy as the plane prepared to land.
There were weak radio signals from the Sea of Okhotsk on the Pacific Ocean, according to Interfax news agency.
According to preliminary information, 28 people were on board, including six crew members.
Meanwhile, a civil defence unit has been deployed to the area to search for the plane and dispatched a helicopter with doctors and medical staff on board.