Colombo: Sri Lankan police said on Tuesday that they have arrested three navy personnel over the 2006 assassination of an ethnic Tamil lawmaker, a killing that had been blamed on Tamil Tiger rebels.

The three men are suspected in the assassination of Nadaraja Raviraj, who was shot dead in his car during the country’s long civil war, police spokesman Ruwan Gunasekara said.

It is the first time Sri Lanka has arrested members of its security forces since new President Maithripala Sirisena pledged accountability for alleged human rights violations committed during the war, which ended in 2009.

Raviraj was outspoken on greater self-rule for minority ethnic Tamils and had explained the Tamil perspective of the conflict in Sinhala, the language of the majority.

The government of former president Mahinda Rajapakse had blamed the assassination on the rebels, but Raviraj’s supporters suspected a government hand.

Gunasekara said the three navy personnel, who were arrested several days ago, are also suspected of killing a policeman and abducting four civilians.

The Tamil Tiger rebels were defeated by government troops in 2009, ending a 26-year war to create an independent Tamil state.

Both sides were accused of committing war crimes, and Rajapaksa’s administration was accused of operating paramilitary groups to kill and abduct rebel suspects and dissidents.

Sirisena was elected president in January, narrowly defeating Rajapakse.