A Delhi-Pune Vistara airlines flight was delayed for around eight hours at the IGI Airport here after a bomb threat call which later turned out to be hoax, security sources and police said. The bomb threat assessment committee declared the call, received at 7:38 am, non-specific or hoax at 2:15 pm. The airline was issued a security clearance for using the aircraft after extensive security checks, the sources said.

Flight UK971 was to depart at 8:30 am and finally left at 4.30 pm, according to police.

The sources said more than 100 passengers and five cabin crew were on board the Airbus A320 aircraft. Vistara said, in a statement, that flight UK971 was delayed due to "mandatory security checks".

A senior Delhi Police officer said a threat call received at the Delhi International Airport Limited (DIAL) control room in Gurugram was transferred to them through the Central Industrial Security Force (CISF).

Following the call, search and combing operations were launched at the terminal 3 of the Indira Gandhi International (IGI) Airport.

"The passengers were de boarded and we checked the aircraft from inside and outside, but nothing suspicious was found. A case is being registered and further investigation is underway," the officer said.

Airport security sources said the caller said "three bombs have been kept in flight no UK971 parked at gate no 42 and they will explode in an hour". The call got disconnected immediately.

All passengers and crew of the flight were de-boarded and anti-sabotage checks were conducted in an isolation bay at the Indira Gandhi International (IGI) Airport, they said.

The bomb threat assessment committee (BTAC) was convened soon after the call was received and bomb detection equipment and sniffer dogs were pressed into service by the CISF while passengers' luggage was sent for re-check, they added.

The airlines said it was cooperating with the security agencies.

"We confirm that the flight UK971, scheduled to fly from Delhi to Pune on 18 August 2023, is delayed due to mandatory security checks," it said.

"In the meanwhile, we are making all efforts to minimise inconvenience to our customers, including offering them refreshments," it said.

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