Airport sources said the incident was reported around 5 pm on Thursday.

Constable Arif Mohammed, of the B-company of CISF, was posted near gate numbers 5 and 6 of the Indira Gandhi International Airport at the time. Airport sources said the fight began when the immigration official, identified by officials as one Inspector Jhakhar, reportedly posted with the Delhi Police’s FRRO branch, tried to get past the security check along with an acquaintance.

“Constable Arif stopped them and asked what they were trying to do. On this, the immigration inspector told him that he (Arif) should not stop him as he belongs to the staff,” police sources said.

Following a row, a fight ensued: “The immigration official allegedly hit the CISF constable when he didn’t allow him to pass without proper checking,” a police source said.

Other security personnel had to step in to check the situation from getting out of hand, the source said.

The matter was reported to senior officers of both departments and inquiries have been initiated. “A preliminary inquiry will be conducted; if found necessary, a departmental inquiry will also be conducted,” the source said.

Sources said CCTV camera footage has been sought by senior officers to assess who was at fault.