A dramatic and unprecedented surge in hoax bomb threats targeting Indian airlines is wreaking havoc on flight schedules, diverting planes and causing widespread disruptions.

Air India passengers arriving in New York from Mumbai on Saturday were delayed by a hoax bomb threat, adding to a string of false alarms the carrier has received this month.

An Air India flight from Mumbai to London Heathrow has become the latest target for a string of hoax threats against Indian carriers. Flight AI129 was approaching the Essex coast after a nine-and-a-half flight from the Indian city. It appeared to be descending for a normal landing at Heathrow.

An Air India flight from Dubai to Jaipur landed safely after a bomb threat turned out to be a hoax. The plane was checked thoroughly and no suspicious items were found.

More than 20 flights received bomb threats this week, leading to diversions and rescheduling of flights and sending security forces into a tizzy.

According to flight tracker Flightradar24, the Air Indian Express plane took off from the Madurai airport at about 1.54pm local time and was due to land in Singapore at about 8.50pm. It only landed at 10.04pm after a delay of over an hour.

More than 90 fake bomb threats have been made against flights operated by multiple Indian airlines this week, Indian media reported Sunday, sparking fear among passengers and global delays.India's IndiGo airline confirmed threats were made against six of its flights on Sunday.

So far this week, more than 70 domestic and international flights of Indian airlines have received bomb threats, with all of them turning out to be hoaxes.

Amid a surge in hoax bomb threats targeting Indian airlines, officials from the Bureau of Civil Aviation Security (BCAS) held a meeting with airline representatives at the agency's headquarters in Delhi on Saturday.