On Sunday, Russian military forces opened fire on three Ukrainian ships off the coast of Crimea, rammed one of them, and seized all three. The ships were manned by 23 crew members. Ukrainian authorities say between three and six have been injured.

Russia claims the boats had illegally entered its sovereign waters, but this is untrue. The Ukrainian vessels—two gunboats and a tugboat—were sailing from Odessa around the Crimean peninsula in the Black Sea, headed toward the Kerch Strait and Mariupol on the north bank of the Sea of Azov. A 2003 treaty between Ukraine and Russia guarantees both nations the right to use the Kerch Strait and Azov Sea for commercial purposes. The same treaty allows either nation to use the waters to transport military vessels so long as the transporting nation notifies the other. A Russian oil tanker nonetheless blocked the ships from passing through the strait, fighter jets passed overhead as if the ships were an invading force, and Russian troops boarded and took control of the ships.