New Delhi, Apr 23 : Officials investigating the sighting of an unidentified radar blip on the Air Traffic Control screen on Tuesday as Prime Minister Manmohan Singh's flight was descending into New Delhi, said on Wednesday that there was no security breach.
An Indian Air Force Dornier aircraft caused the radar blip, they said after their inquiry.
All Standard Operating Procedures (SOPs) were maintained for the security of the Prime Minister's official Boeing-737, which was returning from Ranchi.
The blip was seen on the radar screens of air traffic controllers at Delhi's Indira Gandhi International Airport right behind the Prime Minister's Boeing and appeared to be chasing the VIP plane, throwing IAF, security and aviation agencies into panic.
"There was some form of equipment failure localised in the transponder of an IAF Dornier-228 aircraft that had caused the blip on the screens which seemed to be chasing the PM's plane," Officials said.
"The security of the Prime Minister's aircraft was not endangered. The mandatory twenty nautical miles separation was maintained throughout," they added.
Earlier, Airport Authority of India (AAI) sources said the Dornier was flying behind and above the VIP flight path.