The identity of the deceased could not be known yet.
Tipped off, a team of BGB-2 conducted a drive and challenged a boat carrying three people along no 1 sluice gate of the Naf River, said a press release of BGB headquarters.
Sensing danger, the criminals opened fire on BGB men, forcing them to fire back that triggered a gunfight.
At one stage, all the criminals jumped into the river in a bid to flee.
Later, the BGB members arrested a man with bullet injuries and took him to a local hospital where doctors declared him dead.
Two BGB men were also injured during the incident.
A locally made firearm, 2.10 lakh Yaba tablets worth Tk 6.30 crore, and two bullets of cartridges were recovered from the spot.
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