The monks were detained four days after a mob, including Buddhist monks, vandalised and set afire a showroom of the Fashion Bug clothing chain in the Pepiliyana suburb of Colombo, police spokesman and superintendent Buddhika Siriwardena said.
Police arrested three monks after they surrendered. They will be taken to a magistrate tomorrow, he said, adding that investigations are underway to nab more suspects.
The arrests came after six monks were remanded in police custody on Saturday till April 2. An identification parade for all suspects would be held tomorrow.
"This is a democratic country, non-Buddhists have equal rights and freedoms. While we safeguard the rights of Buddhists, it is the responsibility of the Buddhists to be exemplary and protect the rights of others," he had said.
Bodu Bala Sena, the Buddhist nationalist group, is allegedly leading a campaign which they say targets the growing Muslim extremism in the country.
Less than 10 per cent of Sri Lanka's population of 20 million are Muslim. The majority are Sinhalese Buddhist, while most Tamils are Hindu.