Russia’s Defence Ministry has said that the country’s warship caught the U.S. Navy’s destroyer USS John S. McCain operating illegally in Russia’s territorial waters in the Sea of Japan, but chased it off.

The Ministry said that the Admiral Vinogradov, a Russian destroyer, had verbally warned the U.S. ship and threatened to ram it in order to force it to leave the area.

The U.S ship had immediately returned to neutral waters after being warned off, the Defence Ministry said in a statement.