Ukrainian forces struck the Saki air base in Russian-occupied Crimea overnight, the Ukrainian military said Thursday, confirming an attack previously reported by a source in the Security Service of Ukraine (SBU).

“The defense forces of Ukraine carried out a combined attack on a military airbase near the city of Saka in the temporarily occupied Crimea,” the military said on its Telegram channel.

A SBU source told Reuters that the attack caused “serious damage” to equipment at the base.

Russia has not yet commented on this information.

The Russian military said Thursday morning that it had destroyed 19 Ukrainian drones over Crimea and the Black Sea, but did not provide details on casualties or damage.

The SBU and the Navy of Ukraine carried out the attack at night, according to a source in the SBU.

“Strikes by the Security Service and the Navy hit the target and caused serious damage to the equipment of the occupiers,” the source said, predicting that drones were used first and then Neptune cruise missiles.

The source said at least 12 fighter jets and a man-portable anti-aircraft missile system were at the base in western Crimea, and that the base was also used as a training base for drone operators.

Reuters notes that it could not independently verify this information.

Kyiv said a series of attacks in Crimea last week damaged two Russian patrol ships and destroyed a sophisticated air defense system.

Kyiv said on Wednesday that Ukrainian forces had struck a command post of the Russian Black Sea Fleet near Sevastopol in Crimea.