The 78 crew members on board the Russian navy intelligence vessel were evacuated
A Russian warship has sunk after colliding with a freighter in the Black Sea, off the Turkish coast
The 78 crew members on board the Russian navy's intelligence vessel - Liman - were evacuated.
The Turkish coastguard said they were all rescued after boats and helicopters were dispatched to the area, near the Istanbul coastline.
Shipping agent GAC said the Russian ship and the Togo-flagged vessel - Youzarsif H - collided in fog and low visibility.
Turkish Prime Minister Binali Yildirim called his Russian counterpart Dmitry Medvedev to express his sadness over the collision.
Crews had battled to keep Liman afloat, according to the Russian defence ministry.
It said the vessel "sustained a hull breach due to a collision" some 25 miles northwest of the Bosphorus Strait.
Liman is a former research vessel the Russian navy has transformed into a reconnaissance ship.
In February, military sources told Russian media that it would be observing NATO's Sea Shield exercise in the Black Sea.
More to follow ...