Detectives in separate drives arrested 59 members of "dope gangs" from different parts of the capital yesterday.
Police recovered food mixed with sedatives and knives from them, said DMP Deputy Commissioner Md Walid Hossain.
Among the arrestees, 16 were arrested by DB Wari zone, 10 by Cyber and Special Crime Investigation Department, nine by Mothijheel zone, and eight each by Ramna, Lalbagh and Tejgaon zones of DB police.
Upon interrogation, police learned that the criminals quickly built up rapport through conversation with "targets" at shopping malls, cattle markets, bus terminals and rail stations ahead of Eid, and offered them food laced with sedatives.
Later, when the victim fell unconscious, they looted the belongings and fled, said law enforcers.