Three crew members have died after a Ukrainian general cargoship broke its back and sank off Turkey's Black Sea coast.

The 3,500-dwt Arvin (built 1975) went down off Bartin in poor weather, Turkey's coast guard said on Sunday.

The country's transport ministry said the Palau-flagged vessel had anchored off the port, before breaking into two pieces and sinking.

The vessel "attempted to take refuge at the Bartin port due to poor weather conditions as it carried cargo from Georgia to Bulgaria," Bartin provincial governor Sinan Guner said in a report by state-owned Anadolu news agency.

The cargoship had taken on water before it went down.

Six seafarers have been rescued, but a search was launched for one other, the coast guard said. The crew of 10 was made up eight Ukrainians and two Russians.

Difficult rescue

Six crew have been rescued from Arvin. Photo: Duygu Erel/MarineTraffice

Guner said other merchant vessels had been asked to help, while the Turkish defence ministry sent a ship.

"There are high waves, and because of the waves the [rescue] boat can’t see its surroundings. We are trying to reach them with directions from the shore," Guner was cited as saying.

The Ukrainian news website Suspilne said Ukrainian crew member Vladyslav Zaterka had reported the incident before the vessel sank. He was later rescued, according to his fiancee.

The Arvin is operated by Tesoro Marine of Ukraine.

The ship has no recorded port state control detentions since 2016. Insurance cover is provided by Hydor.