Russia says one of its warships fired warning shots at a Turkish fishing boat in the Aegean Sea to avoid a collision.
A Russian defence ministry statement said the Turkish vessel approached to 600m (1,800ft) before turning away in response to Russian small arms fire.
The captain of the Turkish boat said he was unaware that his vessel had been shot at.
The Turkish military attache in Moscow has been summoned to the foreign ministry over the incident.
Relations remain tense between the two countries since Turkey's shooting down of a Russian warplane.