Sri Lanka's biggest mass grave unrelated to civil war, court hears

Sri Lanka's biggest mass grave predates the country's bloody civil war by hundreds of years, according to an independent carbon dating report unveiled in a court Thursday.

The remains of over 300 men, women and children were found last year at a site in the northern Mannar district, where ethnic Tamil guerrillas fought security forces during a 37-year ethnic war that ended in May 2009.

Sri Lanka's Office on Missing Persons (OMP) funded tests on the remains to determine whether the victims were killed during the conflict, which claimed the lives of at least 100,000 people.

But a Miami-based labouratory concluded that the victims likely died up to 615 years ago -- predating even the first European colonisation of the Indian Ocean island by the Portuguese -- according to testimony in the Mannar magistrates court.

Tamil Tiger rebels and government forces both held Mannar district at different times during the conflict, as did troops from neighbouring India, who were deployed in the country in the late 1980s.

The mass grave in the former war zone was discovered by construction workers.

The OMP, which is independent of the government but has a state mandate, said just over 300 skeletal remains had been found, including the remains of about 20 children.

The office has wide powers to investigate cases of people still missing after the civil war. Both soldiers and Tamil rebels were accused of targeting civilians.

About 19,000 people, including 5,000 security personnel, are still unaccounted for after the conflict, a 2013 government panel said in 2013.