A teenager named Opu was killed in Kamrangir Char's Jhauchar on Friday as his rivals swooped down on him with knives and sticks.
The critically injured 18-year-old was first taken to a local hospital and then to Z H Sikder Women's Medical College and Hospital.
Opu was declared dead when he was brought to the emergency department of Dhaka Medical College and Hospital (DMCH) at 7.20pm.
Inspector Bachchu Mia, in-charge of DMCH police outpost said, "The body has been kept in the hospital morgue for autopsy."
Opu's friend and the locals, who went to the spot to save him, said: "We saw that about 20 to 25 people including Ibrahim and Sanju of the area were attacking him with sticks and knives. Some of us also got injured while trying to rescue Opu."
Earlier, some teenagers from the area had a brawl, they said.
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