Long time misbehavior and unpaid wages behind the murders of seven people on MV Al Bakhera vessel in Chandpur, said Lt Col Munim Ferdous, the spokesperson of Rapid Action Battalion, on Wednesday.

Earlier, a team of RAB-11 have arrested Akash Mandal alias Irfan from Bagerhat`s Chitolmari area over the murders. Akash is the employee of MV Al Bakhera.

In primary quizzing, Akash informed that he went out to buy goods for the vessel. Then he went to a market in Pabna from where he bought some sleeping pills.

Out of anger, which Akash has cherished for a long time, he mixed the sleeping pills with food made for supper without the cook`s knowledge. When the seven, including master Golam Kibria, fell unconscious, Akash hacked all of them with a Chinese machete which was always kept inside the vessel for their safety.

When the vessel was anchored on the Meghna River, Akash himself drove the trawler to the Haimchar area after confirming everyone`s death. Then he escaped in another trawler, Lt Col Munim added.

Meanwhile, a case was filed with Haimchar Police Station on Tuesday night by Mahabub Morshed, owner of the vessel, over the incident.

Five bodies were recovered from MV Al Bakhera at around 3PM on Monday and three people were rescued in critical condition. Later, two died at Chandpur general hospital.

The deceased were MV Al Bakhera master Kibria, cooik Rana Kazi, driver Salauddin, helmsman Aminul Munshi, greaser Sajibul Islam, crewmen Azizul Munshi and Majedul Islam.