Kolkata: Kolkata airport received a call early on Tuesday threatening to blow up Air India’s Kolkata-Guwahati flight, authorities say.

According to officials, a woman introduced herself as calling from Rajarhat — a satellite town adjacent to the airport — and said Air India flight AI 729 from Kolkata to Guwahati would be blown up at 9.30am.

“A bomb threat was received on Air India flight flying to Guwahati from Kolkata. However, the case has been disposed of and action has been taken as per the standard operating procedures,” said Kolkata Airport Director Atul Dixit.

This is the third hoax call that authorities have received in the past fortnight, which severely hampered operations at the international airport.

“This has become a major menace and we have requested the police to investigate the real reasons behind the cases. It is unusual to receive such calls so frequently,” said Dixit.

Even the state secretariat has not been spared from such calls, as it received a call threatening to blow up the building earlier this month.

“In most of the earlier cases we found that the callers were mentally unstable. But it is true that this is the third such call to the airport this month which is unusual,” said an officer of the Kolkata police.

“None of these callers are passengers or have ever travelled on an aircraft. What is the reason for such repeated bomb scare to be investigated,” the police officer added.

Passengers scheduled to travel on the aircraft involved had a harrowing time as the flight was delayed and several additional security checks were conducted to ensure everyone’s safety.

“Though we suspected it was a hoax call, we cannot take any chance in this day and age,” an official of India’s national carrier said.

All airports and major train stations in the country are on high alert since Sunday after the terror attack at Uri Kashmir, where 19 Indian soldiers were killed.

Last year, a passenger was accused of making a similar hoax call to delay his flight, as he was late in leaving home.