KOLKATA: Authorities at the Kolkata Airport on Friday received an email claiming bombs were planted at various places on its premises, triggering a frantic search across the facility, officials said.

However, the mail, which threatened that the bombs would explode at 12.55 . p.m., turned out to be a hoax, they said.

According to sources at the airport, the mail said that the sender's team had kept the bomb at Rameswaram Café but the bomb in Kolkata airport was larger.

The mail also mentioned that bombs were planted in four other airports, and all bombs would blast at 12.55 pm. The mail was sent to the airport manager in Kolkata airport around 11.40 am on Friday.

Security agencies at the Netaji Subhas Chandra Bose International Airport (NSCBIA) conducted a thorough search operation following the email, said Aishwariya Sagar, the Deputy Commissioner of Police, Airport Division of Bidhannagar Police Commissionerate.

"After carrying out an extensive search operation, the security personnel concluded that the threat was a hoax," she said.

Airport authorities, the CISF, and the Bidhannagar Police are jointly carrying out an investigation to determine the origin and sender of the email, the officials said.

"We are in the process of tracking the origin of the email," Sagar said.