Constable Kausar Ali, who shot his co-worker dead while on duty in the diplomatic area of the capital's Baridhara, had mental illness but the doctor concerned had given him a certificate with which he returned to duty.
Inspector General of Police (IGP) Chowdhury Abdullah Al Mamun came up with the remark replying to a reporters' question attending the anniversary ceremony of Highway Police at Rajarbagh police lines on Tuesday.
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Kausar was reinstated to his duty after he was declared fit, the IGP said.
Home Minister Asaduzzaman Khan Kamal was present as the chief guest at the event.
He also spoke about the mental health of the police at the event.
Baridhara shooting: Constable Kawsar Ali placed on 7-day remand