Lt. Col. Abdullah Al Momen, commanding officer of RAB-1, said the RAB members conducted an operation at Chandpara to arrest Shahin, acting on a tip-off that he was staying there alone.
But when the law enforcement reached the spot, some 10 people, including Shahin, opened fire on them, forcing them to shot back. At one stage Shahin was shot in his leg.
He was taken to Mugda hospital in Dhaka after detention, the official said, adding that he succumbed to his injuries at the hospital.
The body has been kept at the Dhaka Medical College Hospital (DMCH) morgue.
Rashedul Islam, younger brother of the deceased, said he heard the news of his brother’s death, but had no idea how it happened.
During conversations with family members and at least three residents of the locality, it was learnt that Shahin went to ward no. 1 after leaving his home in a hurry on Thursday noon. Later, a shoot-out took place there between two rival groups.
Locals and police sources said Shahin used to control three drug peddling centres in ward-6 and 7 in Chandpara area. He was a close associate of upazila Awami League executive member Bazlur Rahman and would identify himself as a Swechchha Sebok League leader.
Shahin had a rivalry with another drug peddler of the area, Joynal Abedin, over establishing supremacy.
A man -- Shamsu, a resident of the locality -- was killed when the two groups engaged in a clash in Chandpara in July last year. His family members held Shahin and his associates responsible for the death.
Joynal Abedin has now been languishing in jail in a case. RAB arrested Raju Ahmed alias Raja, a close associate of Shahin, with arms in an operation on 27 September. Shahin had been at large until he resurfaced recently.