State Minister Assaduzzaman Khan Kamal on Monday said killers of SP Babul Akter’s wife will be brought to book by any cost.The minister said this to journalist in a press briefing at secretariat on International day against drug Abuse and illicit trafficking, about the drama after questioning Babul Akter over his wife murder.He said police has arrested one or two suspected killers and police will arrest the killer by any coast.On 5 June, unidentified miscreants gunned down Mahmuda Khanam Mitu at the city’s GEC intersection while she went there to drop her son, Mahir Akhter, 7, for a bus to Chittagong Cantonment Public School and College.