French national Thierry Dornaudent, a key member of a Lake Gardens-based NGO, and two others were arrested on Thursday for thrashing a 16-year-old inmate of an orphanage run by them.

Officers of Lake police station took Thierry and the other two — the manager of the NGO and another employee — in custody after the victim lodged a complaint.

Police said the trio beat up the boy after learning that he had sexually abused an 11-year-old boy, also an inmate of the home, on Tuesday night.

“Thierry and the other two came to know about the incident the next day, summoned the boy and started thrashing him,” said an officer of Lake police station.

Local people informed the cops about commotion in the orphanage. “We went there to inquire what was going on. The boy complained of being beaten up by Thierry and the others,” said the officer.

The police, however, have registered two separate cases. “We have also lodged a complaint against the boy for sexually torturing a fellow inmate,” said Jawed Shamim, the deputy commissioner (south).