The excavation of the largest mass grave discovered in Sri Lanka was temporarily halted on March 8 after Mannar Magistrate Court acknowledged a disparity between the carbon dating of the remains and the  views of investigators.

Six bone samples from Sri Lanka’s largest mass grave were more than 500 years old, according to carbon dating carried out by the Beta Analytic lab in Florida.

On Thursday, the Mannar Magistrate publicized the findings, which deemed that the samples belonged to the period between 1477-1719. The report and findings were then included in the case file as a public dossier.

The magistrate was set to hold a meeting with investigators and relevant stakeholders on March 13 to decide the future of the investigation, but the meeting has now been postponed until March 22.

The mass grave is one of several sites uncovered around Sri Lanka in recent years. Other sites have been discovered around the east coast town of Batticaloa, and another in the central town of Matale.

Informed sources told Asia Times that the samples sent for analysis were ‘utterly contaminated’ and have led to the final results that have caused confusion among the investigators. From artifacts recovered from the site, the remains could not have been more than 30 years old, sources said, meaning that the origins of the grave date back to the height of the island’s civil war.

According to the Consultant Judicial Medical Officer of Mannar District and lead investigator, Dr. WRA Saminda Rajapaksa, 335 individual remains were recovered from the site. Some 29 were children.

Rajapaksa said that given the high profile of the discovery, an official interpretation of the carbon dating findings has to be requested from Beta Analytic lab before the meeting with the magistrate next week.

“All the samples that were collected, were collected randomly,” said Rajapaksa. “There were queries as to why we are sending samples for analysis, at the midpoint of the excavation. Our reason was that, given the site was located on a loose soil area close to the sea, digging further put nearby buildings at risk of collapse.

“Apart from that there were other reasons. Contamination wise, all samples go through some degree of contamination once they are removed. This case was high profile and we wanted to conduct it with the utmost transparency and with no influence from any observer parties.”

The mass grave, found in the middle of the Tamil majority-Mannar town, Northern Province, attained widespread attention following its discovery in March 2018.

The remains were first suspected to be of human origin when a private soil inspector observed the bone-like material found in a soil sample. He received the sample for analysis from a construction company that had intended to build a supermarket.

The discovery of 300-odd remains makes it the largest mass grave site in the country.

Six samples recovered from the site were sent to Beta Analytic late last December, for carbon dating testing, to ascertain the time period of the samples.

The results were received by the group of investigators led by Rajapaksa early this March, exactly one year since the discovery of the site. It was promptly produced before the Mannar Magistrate’s Court.

To assist with the forensic analysis at the scene, Raj Somadeva, a Forensic Archaeological Consultant Professor at the University of Kelaniya, was called in. Somadeva has previous experience in investigating two other mass graves in the country.

He emphasized that the confusion is a result of the various opinions that has surfaced following the publication of the results. He said that it was not traditional to conduct a carbon dating tests prior to completing the excavation of a mass grave.

Somadeva has vehemently rejected the carbon dating results submitted by Beta Analytic relating to the Mannar mass grave.

“There is a non-compatibility between materials and artifacts we unearthed from the mass grave and the results the American laboratory have given us. Therefore, it is difficult to accept this carbon dating,” he said.

He also pointed out that the skeletal remains had been soaking in salty water for a long time, thus altering their chemical composition.

The mass grave gained attention when the Office of Missing Persons inquired about the family members who had gone missing during the civil war and post civil war period. The office, together with several other non-governmental organizations with similar interests, acted as observers in the investigation.

The Office of Missing Persons tweeted:

According to Somadeva, the first literal reference to the site location was made in 1782 in a map by a Dutch geographer. The original map is currently curated at the Royal Archives in the Netherlands and a copy has been requested by the research team.

Similarly, the Survey Department of Sri Lanka was brought into the research to obtain other maps and extracts of field notebooks from the colonial age to get a better understanding of the history of the location.

The Mannar Urban Council and Census and Statistics Department were also consulted to make inquiries regarding the recent history.

Various reports have suggested the grave site area had housed a private bank during the war, while other reports have alleged that a cemetery was located there.

Still, many speculate that the grave site holds Tamil Christian converts who were killed by Cankili II, also known as Segarasasekaran VIII (1617–1619) during a massacre.

However, most of these stories will remain nothing more than a speculation until the official report is submitted.

Somadeva said all the material, maps from 1910, 1929 and 1936, refer to the grave site location as the “market square” – a notion that has not changed with the course of time as the area is still referred by locals as the “grand bazaar.”

The research team found jewelry, coins, clothing, weapons, and projectiles, among other things at the grave site. Rajapaksa and Somadeva have noted that a large quantity of pottery, blue colored porcelain, a number of beads, cellophane papers and two circular ring-like objects were found from the site. They will be analysed to determine their association with the skeletal fragments.

Somadeva previously said that the site had shown natural signatures of a grave site as well as the chaos of discarding bodies expeditiously.