At least two militants have been killed in “Operation Twilight” at Atia Mahal in Sylhet, claimed Bangladesh Army.Brig Gen Fakhrul Ahsan, spokesman of the operation, revealed it at a press briefing at 5:00pm on Sunday.The raid has been going on since last Friday.Earlier, six people including police were killed and many civilians were injured in a blast outside of the building which is surrounded by law enforcing agencies.IS claimed the responsibility of the blast.