Somali pirates have freed a Malaysian tugboat and its 11 Indonesian sailors after a ransom was paid to end the second-longest hostage situation off the coast of Somalia, a maritime watchdog has announced.

The tugboat TB Masindra 7 and its attached Indonesian barge ADM1 had been operating under a contract from French oil giant Total when it was seized eight months ago on 16 December, said Kenya-based Ecoterra International.

Ecoterra said a lack of cooperation between the Malaysian and Indonesian ship owners meant the case dragged on for months, writes AFP.

About 200 sailors and at least 12 ships are still being held in the region, according to local sources.

Somali pirates attacked more than 130 merchant ships last year, according to the International Maritime Bureau.