"So far 150 suspected rioters were arrested and a manhunt is on for others... law enforcement agencies have been asked to enforce a strict vigil for against outbreak of any fresh violence," home minister Mahiuddin Khan Alamgir said.
He said security agencies were particularly asked to enforce a vigil against Myanmar's Muslim Rohingyas who took refuge in Bangladesh after an ethnic conflict with majority Buddhist community at their home in eastern Rakhine state.
Additional police superintendent of Cox's Bazar Babul Akhtar said 118 suspects were arrested from Ramu and adjacent areas alone while police chased and tracked them down also at the port city of Chittagong.
"Most of the suspects were arrested from areas outside Ramu as the rioters fled their homes to evade justice," Akhtar told PTI over phone.
Besides police, the authorities have deployed anti-crime Rapid Action Battalion, Border Guards Bangladesh and army personnel in the affected areas.
Meanwhile, Prime Minister Sheikh Hasina ordered a high-level probe to identify the perpetrators of the attacks.
"An investigation is going on at the highest level to find out those associated with such a heinous act. The law enforcers have been instructed to handle firmly with any such situation," she said in New York on the sidelines of UNGA session.