A gang of seven Somalian pirates were in detention yesterday after the crew of a Hellenic Navy frigate thwarted their attempt to hijack a German oil tanker south of Yemen, the Merchant Marine Ministry said. The frigate Psara, which has been patrolling pirate-infested waters off Somalia for months, responded to a radio call for help issued by the FGS Spessart on Sunday afternoon. The German vessel issued the call after spotting a speedboat with the Somalians approaching. According to ministry sources in Athens, Commodore Antonis Papaioannou, the commander of the European Union’s Operation Atlanta, immediately ordered the frigate to intercept the speedboat and dispatched a helicopter to monitor the operation from the air. The pirates were handed over to a German frigate serving in the EU force. Several Greek-owned cargo ships have been attacked by pirates off the coast of Somalia this year.