A bus tyre burst near Indira Gandhi International Airport on Thursday sent emergency services into a tizzy after it was reported as an explosion, baring the taut mood in the capital in the aftermath of the Red Fort blast.

Delhi is on high alert after the car exploded on Monday, which the Centre has called “a heinous terror incident, perpetrated by anti-national forces”.

The Delhi Fire Services received a call at 9.18am on Thursday from a person driving towards Gurgaon that an explosion had been heard near Radisson Hotel in Mahipalpur, adjacent to the airport.

Television channels reported that “blasts” were heard near the airport. Three fire engines were seen near the hotel, and locals stayed indoors. Following the TV reports, several people checked in on friends and family in the city. The police were, however, quick to quash rumours.

Delhi police posted on X at 11.28 am: “During local enquiry, a guard informed that the rear tyre of a DTC (Delhi Transport Corporation) bus going towards Dhaula Kuan had burst and so the sound had come.”

On Wednesday, security agencies were on their toes after five airports, including Delhi and Mumbai, received hoax bomb threats, leading to flight delays. On Thursday, another hoax threat was reported on an Air India Toronto-Delhi flight.

An Air India spokesperson said: “A security alert was received on Air India flight AI188 during its cruise from Toronto to Delhi on November 13. On-board crew carried out all the laid-down security drills, keeping passenger safety and security as top priority. The flight has landed safely in Delhi and has been parked for the mandatory security checks by the security as per the protocol. All passengers and crew have disembarked safely.”

Airlines have asked passengers to report early, and queues in Metro stations are longer than usual due to intense checking.