Two Buddhist monks and eight other men were arrested on Wednesday, accused of sexually abusing 11 children orphaned by the island's 19-year civil war, an official said.
Investigations revealed that the children, aged between nine and 13, had been sexually abused over a period of time at an orphanage where the men worked, said Prof. Harendra de Silva, head of the National Child Protection Authority.
"There are maybe more who have been abused and we are continuing investigations," de Silva said, after a special police unit attached to the authority arrested the suspects.
The men, including the saffron-robed monks, will be produced before a magistrate and held in custody for further investigation, he said.
Child abuse in Sri Lanka is a non-bailable offense and with a maximum 10-year prison sentence.
The Liberation Tigers of Tamileelam began fighting the government in 1983 to create a separate state for the island's 3.2 million minority ethnic Tamils.
Nearly 65,000 people died in the conflict before a cease-fire was agreed in February 2002.
The children's home where the suspects worked was established to care for thousands of children from all over the country who lost their families during the war.