Twelve more people were arrested in the past 24 hours over the vandalism and arson carried out by Hefazat-e-Islam activists and supporters in Brahmanbaria last month, police said Monday.
The arrests were made from different parts of the district after inspecting video footage of the violence, according to the special branch of district police.
So far, 55 cases have been filed and 310 people arrested over the rampage, the police said.
On March 27, at least five people were killed and around 50 others, including 25 policemen, injured in clashes between the law enforcers and locals during Hefazat's demonstrations at Nandanpur in Sadar upazila.
They had staged the protests against Indian Prime Minister Narendra Modi's Bangladesh visit.
The next day, during Hefazat's countrywide dawn-to-dusk general strike, against police action on their anti-Modi processions in Dhaka, the organisation's activists in Chattogram and other districts set three buildings on fire, including the land office in Brahmanbaria Sadar upazila.
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They had also attacked a Chattogram-bound train at Talshohor Rail Station in Brahmanbaria town.
Also, the Hefazat supporters vandalised several private and government establishments, including the municipality building, Alauddin Music Academy, and Foirtala Bus Stand in Sadar upazila.
They had also attacked Brahmanbaria Press Club and confined some journalists to the premises.