A gang tried to loot Marabhola outpost at 9:00pm. Police opened fire and the gang fired back. Ali Ahmed, an alleged pirates' gang leader, was killed during the hour-long firefight and the three other wounded were held from the area, police said.

Police recovered Ali's body and a rifle, said Tariqul Islam, deputy forest officer of eastern wing of the Sundarbans Forest Division.

The injured were being treated in police custody, he added.