Berlin - German naval forces detained seven pirates who attacked a German supply tanker off the coast of Somalia, a defence ministry spokesman said Monday.

The pirates opened fire on the civilian-crewed vessel Spessart Sunday afternoon, but were driven off by a "mobile protection element" on board, the spokesman said.

A German and Greek naval unit in the vicinity gave chase and apprehended the pirates, who were later taken on board the German frigate Rheinland-Pfalz, the spokesman added.

The vessels are part of the EU Atalanta mission established to counter piracy off the Horn of Africa.

On March 10, Germany handed over over to Kenya nine Somali pirates who attacked a German freighter in the Gulf of Aden.

Sunday's incident came a day after the release of a German gas tanker hijacked in January by pirates in region. The 100-metre-long Longchamp and its crew were able to resume their journey, apparently after a ransom was paid, reports said. (dpa)