The six-strong crew of a Danish-flagged freighter was Friday feared abducted by pirates in the Gulf of Aden.
Turkish naval forces from NATO's anti-piracy operation boarded the vessel Thursday but found no sign of the crew, daily Politiken reported, citing NATO sources, DPA reported.
The 67 metre-long vessel, the Leopard, was shot at Wednesday while off the coast of Oman. There has since been no contact with the crew, which comprises two Danish nationals, including the captain, and four Filipinos.
If the crew have indeed been abducted, it would mark a change in tactics by Somali pirates, said the online maritime news site TradeWinds. Hijacked vessels are usually taken to the coast of Somalia.
The European Union's anti-piracy Operation Atalanta, which is deployed off the coast of Somalia, estimates that pirates are currently holding about 30 vessels and 600 crew members hostage.
A Danish vessel, the Danica White, was held by pirates for 83 days in 2007.