The Thai military played a larger role in the killing of civilians during political unrest in Bangkok this year than officials have acknowledged, leaked state documents seen by Reuters show.

A preliminary state probe into political violence in April and May concluded Thai special forces positioned on an elevated railway track fired into the grounds of a Buddhist temple where several thousand protesters had taken refuge on May 19.

Three of six people shot dead at the temple were likely killed by troops, the investigation found, directly contradicting statements by the Thai military, which has denied soldiers were responsible for the killings at the temple.

The report said there was not enough evidence to come to a conclusion about who was responsible for the other three deaths in the temple, but it said all six victims were hit by high-velocity bullets.

“There is a reasonable amount of facts, evidence and witness accounts to believe that (three) deaths resulted from security officials’ actions on duty,”” the investigators said, recommending that police look into the deaths further.

The report quoted soldiers involved as saying they fired warning shots and cover fire, and had been shot at from the temple.

The findings by Thailand’s Department of Special Investigation (DSI) are likely to embolden the “red shirt” anti-government protest movement challenging the legitimacy of Prime Minister Abhisit Vejjajiva, who in June blamed armed elements among the protesters for the temple deaths.

The full report is available here.