At least 11 people have died in a fire involving two Tanzanian-flagged cargo vessels in the Black Sea near the Kerch strait.
Authorities said Russian rescuers are trying to reach sailors who jumped overboard and 14 people have so far been rescued.
One ship is a gas tanker, and the fire reportedly followed an explosion, which set the other vessel on fire.
They were named as the Kandy, with a crew of 17 from Turkey and India, and maestro, with 14 sailors.
The fire broke out when one vessel was transferring fuel to another, Russian Maritime Agency spokesman Alexei Kravchenko said, adding that this had then forced several crew members to jump overboard.
Rescue workers reportedly witnessed a further three people struggling in the water, who most likely had drowned.
Reports say no signal from either one of the two captains’ had been received.
The Kerch strait is a focus of tension between Russia and Ukraine.