A marine drone of the type used in the war in neighbouring Ukraine self-detonated on Friday (June 5) in Romania's Black Sea port of Constanta near an oil terminal, without causing any casualties, the defence ministry said.

Audio of the explosion can be heard on video followed by thick black smoke rising above the water.

The port was being evacuated, residents along Romania's Black Sea coast were warned to take cover, and two helicopters were surveying the area for any further drones, deputy Interior Minister Raed Arafat said.

Three more maritime drones were found on the Romanian coast after an explosion in Constanta port, news website Digi24 said on Friday, citing unnamed sources.

The explosion comes a week after a Russian drone crashed into an apartment building in the southeastern Romanian city of Galati, near the border with Ukraine, injuring two people - the first time in the Russia-Ukraine war that a drone struck a densely populated area in a NATO state.

Romania, a NATO and European Union member, shares a 650-km (400-mile) border with Ukraine and has reported 28 incursions into its airspace by Russian drones since Moscow began attacking Ukrainian ports on the Danube, the defence ministry has said.

Ukrainian drone fragments have also landed on Romanian territory.

DESCRIPCIÓN DE IMÁGENES

CONSTANTA, ROMANIA (JUNE 5, 2026) (OBSERVATOR ANTENA1 - Must on screen courtesy OBSERVATOR ANTENA1. No Use Romania.)

1. SHIP IN PORT (AUDIO OF EXPLOSION) / THICK BLACK SMOKE RISING ABOVE WATER, SHIPS DOCKED NEARBY