A Mumbai-bound IndiGo flight from Chennai received a bomb threat message on Tuesday, but it landed safely here, an airport source said.

The bomb threat message was received at the private airline's call centre in New Delhi, the source said without delving into specifics.

The flight landed safely at the Mumbai airport at 10.30 pm, he said.

"IndiGo flight 6E 5149, operating from Chennai to Mumbai, had received a bomb threat. Upon landing in Mumbai, the crew followed protocol and the aircraft was taken to an isolation bay," the airline said in a statement.

All passengers have safely disembarked the aircraft, IndiGo said.

"We are working with security agencies and post completion of all security checks, the aircraft will be positioned back in the terminal area," it added.

Earlier in the day, as many airports, including in Varanasi, Chennai, Patna and Jaipur, received bomb threat emails, prompting authorities to scramble contingency measures and carry out anti-sabotage checks that lasted hours, and each of them was found to be a hoax, official sources said.

Security was beefed up as agencies swept the airport terminals after the emails were received around 12.40 pm from the ID exhumedyou888@gmail.com.

The airports in Varanasi, Chennai, Patna, Nagpur, Jaipur, Vadodara, Coimbatore and Jabalpur were among those that received the hoax threats, as per the officials.

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