The main gas supply line to Narsingdi was damaged during construction work on a drain, according to Titas Gas authorities
Executive Magistrate Sarwoer Alam said he headed a drive in a wholesale fish market in Jatrabarhi late on Saturday night following a tip-off that Hilsha fry was being delivered there.
The deliveries continued even the drive was under way after midnight, he said.
He said they arrested seven people and seized around 8 tonnes Jatka. Each of the arrested people was handed two-year jail term.