Law enforcers arrested 15 people on early Wednesday over the petrol bomb attack on a bus in Comilla that killed seven people and injured sixteen others on Tuesday.

Police said four shibir leaders and activists were shot during the raid. The four injured Shibir men are Chauddagram (North) Shibir president Borhan Uddin and three members Yusuf, Abu Sufiyan and Abdul Alim.

Chauddagram Police officer-in-charge Abdullah Al Mahfuz said Ansar has been deployed in Chauddagram to ensure security on highways. A three member committee headed by additional district magistrate Golamur Rahman, has been formed to investigate the arson attack incident.

The police administration has declared a bounty of taka one lakh for handing over the miscreants involved in the incident.