The pilot of the chopper had given a 'May Day call' (emergency call) before the crash and lost radio and radar contact after that, IAF spokesperson said in Delhi .
The IAF aircraft had on board two pilots and five air warriors. There are no survivors, he said.
The chopper had taken off from Bareilly at 1553 hours and crashed approximately around 1657 hours, the spokesman said.
The IAF has ordered a Court of Inquiry and teams have been rushed to the crash site in Sitapur.
A Wing Commander, Squadron Leader, Junior Warrant Officer, Sergeant and an LAC along with two Corporals were killed in the crash.
Sub Divisional Magistrate, Sidhauli, A K Srivastava said that the chopper was engulfed in fire as it crashed in Manipurwa in Ataria area.
District Magistrate, Sitapur, JP Singh said that the helicopter was heading towards Allahabad when it crashed. Sitapur is nearly 160 km from Bareilly and over 90 km from Lucknow.