At least 11 sailors have died after two ships caught fire while moving through the Kerch Strait separating Crimea from mainland Russia - the location of the latest escalation in tensions between Russia and Ukraine in November - after one of them was apparently rocked by an explosion the Russian Maritime Agency said. One vessel was "allegedly struck by a blast" RT reported, which caused the fire that then spilled over to another ship, an official with the Russian Maritime and River Transport Agency said.

Clouds of black smoke could be seen billowing over a vessel engulfed by a blaze on YouTube footage, which shows the scene of the incident. Another ship can be seen floating nearby.

The fire reportedly broke out as the two ships were transferring fuel from one to the other. According to RT, approximately three dozen sailors managed to escape the burning ships by jumping into the sea but at least 11 people died in the incident and 12 have so far been rescued from the sea.

The crews of the affected ships included Turkish and Indian nationals, the emergency services said, adding that there were no Russian sailors. Turkey confirmed that 16 of its citizens were aboard the affected vessels.

Emergency services said that between eight and ten ships have been sent to the rescue and are picking up the sailors. The explosion might have been caused by a safety rules violation during the fuel transfer, according to some reports.

One of the ships was a liquefied natural gas carrier and another one was a tanker; both vessels were flying Tanzanian flags.

According to the director of the Crimean Sea Ports, the maritime traffic through the strait was not affected by the incident and navigation across Kerch remains open.