(CNN) -- Four teenagers have been arrested on suspicion of arson after a fire at a Muslim boarding school near London, police said Monday.
Two of the teens are 17, and the other two are 18. They were arrested late Sunday night.
The fire inflicted only minor damage to the Darul Uloom School in Chislehurst on Saturday night, the Metropolitan Police said. Two people were treated for smoke inhalation.
The 128 students and staff evacuated during blaze were allowed to return Sunday, police said.
The fire is the latest in a series of suspicious incidents at Muslim institutions since the May 22 killing of a British soldier on a London street. Anti-Muslim actions and angry social media sentiment have emerged in Britain since the killing, including fires at mosques in north London and in the east coast city of Grimsby.
Prime Minister David Cameron's government has formed a task force to examine the dynamics behind extremist groups in the country in the wake of the killing, which triggered demonstrations by a far-right group in several cities. The Metropolitan Police said it had increased patrols around "potentially vulnerable locations" in the area around the school and around London.