Russia and Ukraine traded accusations over an incident at sea Sunday near the disputed Crimean Peninsula, increasing tensions between both countries and prompting Moscow to block passage through the Kerch Strait.

Russia’s coast guard said that three Ukrainian navy ships made an unauthorized crossing through Russian territorial waters, while Ukraine alleged that one of its boats was rammed by a Russian coast guard vessel.

The Kerch Strait is a narrow body of water nestled between Crimea and the Russian mainland.

The incident began after the Ukrainian navy claimed a Russian coast guard vessel rammed one of its tugboats, which was travelling with two Ukrainian navy artillery boats from Odessa on the Black Sea to Mariupol in the Sea of Azov, via the Kerch Strait.

“Russian coast guard vessels … carried out openly aggressive actions against Ukrainian navy ships,” the Ukrainian navy statement said. It said a Russian coast guard ship damaged the tugboat’s engine, hull, side railing and a lifeboat.

The statement added that Russia had been informed in advance about the planned journey.

Russia then blocked off the strait. The move comes after months of growing tensions between Ukraine and Russia, which annexed Crimea from Ukraine in 2014 and has steadily worked to increase its zone of control around the peninsula.

The Kerch Strait is the only passage into the Sea of Azov beyond it. The strait is crossed by the recently completed Kerch Bridge, connecting Crimea to Russia. Transit under the bridge has been blocked by a tanker ship, and dozens of cargo ships awaiting passage are stuck.

source: AP