Pirates today fired rocket-propelled grenades and automatic weapons at a 330-metre long oil tanker sailing 1,000 miles from the Somali coast.
The European Union's naval force patrolling shipping lanes around Somalia said it was the longest-range attack Somali pirates had ever launched.
The force, known as EU Navfor, said in a statement that the pirates responsible for the attack on the Hong Kong-flagged BW Lion had operated from two fast attack skiffs.
The master of the ship increased speed and employed evasive measures to escape the pirates. The attack happened 400 nautical miles north-east of the Seychelles.
EU Navfor said the French warship, FS Floreal, and a maritime patrol aircraft from Luxembourg which was based in the Seychelles, were searching for the pirates.