The Detective Branch (DB) of Police have arrested a close aide of Nur Hossain, the prime accused of the seven-murder case, from Brahmanbaria on Saturday morning.
The arrestee, Ali Mohammad, was the cashier of Nur Hossain's "illegal" money.
Investigation Officer in the seven murder case Mamunur Rashid Mondol said: "Acting on a tip off, DB personnel arrested Ali Mohammad from Akhaura Aulia Bazar area of Brahmanbaria.
"Ali Mohammad is one of the three close associates of Nur Hossain. The arrested accused disclosed his name duing interrogation."
Ali went on hiding after the seven murder incident in Narayanganj.
Police will produce Ali before Narayanganj Senior Judicial Magistrate Court on Sunday, police sources said.
Narayanganj City Corporation panel mayor, along with six others was abducted on April 27. Later, their bodies were found floating in River Shitalakhya on April 30.
Nazrul's wife filed an abduction case against Nur and four others on April 28. On June 14, police arrested Nur Hossain with three of his accomplices in Kaliakair area under Baguhati police station of Kolkata.