The suspended SI is Hasan Uddin of Bandarbazar police outpost.
Sylhet Metropolitan Police (SMP) confirmed the matter in a press release in the afternoon.
Members of Police Bureau of Investigation (PBI) arrested constable Titu Chandra Das, who was also suspended over the death, from Sylhet police lines on Tuesday.
On October 11, Rayhan Ahmed, 34, a resident of Akharia in Sylhet city, was beaten to death in police custody, said the family of the victim.
His wife Tahmina Akter Tanni filed a case with Kotwali Police Station the following day accusing a number of unidentified people.
Besides, the authorities on October 12 suspended four policemen, including the in-charge of Bandarbazar Police outpost Sub-Inspector Akbar Hossain, in connection with the death of a man ‘in police custody’ in Sylhet.
Three policemen have been withdrawn in this connection on the same day.
Police rejected the allegation and said Rayhan was caught by locals of Kastghar area during the robbery and was lynched.
Besides, the case has been transferred to the Police Bureau of Investigation.
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