ISLAMABAD - The bomb threat at Benazir Bhutto International Airport in Pakistani capital turned out to be a hoax and the airport was cleared after a search operation, officials said Tuesday.

The spokesperson of Civil Aviation Authority said that a state of emergency was declared at the airport after the airport authorities received an anonymous call from London on Tuesday morning, claiming that there are bombs on two of the international flights ready to take off on the runway.

He said that the bomb hoax delayed five flights as the airport was temporarily closed and a flight coming from Doha was diverted to the country's northwest Peshawar city.

The bomb disposal unit searched the five planes and all the passenger baggage but found nothing. After this, the airport was cleared and routine flight operation was resumed.

Security has been put on high alert at the airport and extra contingent of force deployed to avoid any untoward situation, said the spokesperson.