Rajiv Gandhi International Airport received three bomb threats targeting flights arriving from overseas and within India, airport sources said on Monday, prompting the activation of emergency protocols even as all aircraft landed safely.

The airport received emails late Sunday night warning of explosives on British Airways flight BA 277 from Heathrow, Lufthansa flight LH 752 from Frankfurt, and IndiGo flight 6E 7178 from Kannur. The two international flights landed in the early hours of Monday, while all crews and passengers were taken through security checks.

“Standard safety protocols were initiated for all three aircraft,” airport sources said. The procedures included isolating the aircraft, screening baggage and passengers, deploying sniffer dogs, and keeping fire engines on standby.

The incident follows a series of similar threats last week, when RGIA received bomb alert emails for the Dubai–Hyderabad Emirates flight and IndiGo’s Madina–Hyderabad and Sharjah–Hyderabad services.

Madina–Hyderabad was diverted to Ahmedabad airport.