TRIPOLI (AFP) - Libya's internationally recognised government attacked a Turkish-owned cargo vessel from ground and air, killing a seaman, after it entered territorial waters "without permission", a lawmaker said Monday.

"The air force called on it several times to turn back but it failed to comply," said the member of the recognised parliament based in the eastern port city of Tobruk.

He said the air force had then bombed it when it approached the coast near the port of Derna, an extremist stronghold.

It was the second deadly strike against merchant shipping by the Tobruk government's air force this year, and drew an angry response from Ankara. The Turkish foreign ministry said it had lodged a protest with the Libyan authorities over the "atrocious" attack on the Cook Islands-flagged ship which had been travelling to Libya with a cargo of gypsum from Spain.

It said the vessel was shelled by coastal artillery on Sunday when it was 13 nautical miles off Tobruk and that it then came under air attack twice.

"The third captain of the ship lost his life, several of the crew were injured and the ship was damaged," a foreign ministry statement said.

The Tobruk government, which no longer controls Tripoli but is recognised by the international community, regularly accuses Turkey and Qatar of backing its Islamist rival based in the capital.

It is the second time this year that it has drawn international condemnation for attacking shipping near Derna. In January, its aircraft bombed a Greek-operated oil tanker off Derna, killing two crewmen - one Greek and one Romanian.

Washington strongly condemned that attack which it described as an "escalation of violence in Libya against civilian commercial interests".

Libya has had rival governments since August last year when an Islamist-backed militia alliance overran the capital, prompting its opponents to take refuge in the east.