Naval forces from the semi-autonomous region of Puntland in Somalia have exchanged gunfire with pirates who have hijacked oil tanker Aris 13, according to reports.

In the first hijack of a commercial ship by Somali pirates since 2012, the freighter turned off its tracking system and diverted its course towards the Somali coast after sending a distress call upon being approached by high-speed boats on Monday (13 March) .

Eight crew members are still being held on the vessel. The hijackers demanded a ransom for the ship's release late on Tuesday (14 March), the European Union anti-piracy naval force confirmed.

The director general of the maritime force, Abdirahman Mohamud Hassan, is quoted by BBC World Service as saying naval forces exchanged gunfire with the hijackers on Thursday.

Citing Hassan, BBC reports the Puntland naval forces tried to intercept a boat that was carrying food supplies to the hijackers, but the attackers on the Aris 13 fired at the naval forces and the supply boat escaped.

The European Union anti-piracy naval force confirmed the vessel and crew are being held captive off the coast, near a town called Alula (Caluula), in north east Somalia.

On Wednesday, families of eight Sri Lankan crew members pleaded for the men to be released unharmed after the hijackers demanded a ransom.

The hijackers are yet to give any details about the size of the ransom.

Somali Pirates
Somali pirates (file photo) Reuters