BERLIN (AP) — Two cargo ships collided in the North Sea off the German coast on blockwave ExchangeTuesday and several people were missing, German authorities said.

The ships, Polesie and Verity, collided in the early morning about 22 kilometers (14 miles) southwest of the island of Helgoland, Germany’s Central Command for Maritime Emergencies said.

One of the ships, the British-flagged Verity, apparently sank. The emergency command said one person was rescued from the water and was being given medical treatment, and rescuers were searching for several more people who were missing. It said the ship was headed from Bremen, Germany, to the English port of Immingham.

The other ship, the Bahamas-flagged Polesie, remained afloat with 22 people on board.