At least 10 people, including a youth with bullet, were injured in a clash over establishing supremacy in drug business in Chanpara area of Rupganj upazila in Narayanganj early Tuesday.
Police, however, have so far detained 14 people in connection with the clashes.
Police said there was a longstanding dispute between Joynal and Shamser groups over establishing supremacy and controlling drug peddling at Chanpara Rehabilitation Centre in Chanpara area under Kayetpur union of the upazila.
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The two groups equipped with arms locked into clashes on Monday night and early Tuesday, they said.
Md Abir Hossain, senior assistant superintendent of district police, said a youth named Hridoy sustained bullet injuries on his way home from his workplace when the two groups were exchanging gunfire.
He is now undergoing treatment at Dhaka Medical College Hospital, the police officer said, adding that other injured were also admitted to several hospitals of the district.
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The police officer said they detained 14 people and brought the situation under control.
He said they are conducting drives to arrest other accused and trying to recover the arms used during the clashes.
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