Russia "fired warning shots" at Turkey, the country's defence ministry said on Sunday, after two ships came within 500 metres of each other in the Aegean Sea.
A destroyer warship named Smetlivy was forced to fire warning shots at a Turkish vessel when it could not be contacted, in order to avoid a collision.
According to the Interfax news agency the vessels passed within 500 metres of each other. The Turkish vessel, reported to be a fishing boat according to some local media reports, then changed direction in response to the shots from "small arms" and "from a range that is not lethal", Russian authorities said.
Turkey's military attache in Moscow has been summoned to the Russian foreign ministry over the incident.
Tensions between the two countries remain high after a Russian jet was shot down by Turkish warplanes near the Syrian border in November.
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