Security has been stepped up at the Rajiv Gandhi International Airport and other airports in Andhra Pradesh following an Intelligence Bureau report issuing a warning that terrorists might hijack aircraft to demand the release of Mohammed Afzal Guru, who has been sentenced to death in the Parliament attack case.

Speaking to UNI, Airport Director R K Singla said the security at airports were further strengthened. The passengers were being frisked and luggage thoroughly checked, he added.

"Liquids are only allowed on board after the verification," he added.

Stating that security agencies were extra cautious because of the heavy rush of Haj pilgrims at airports, Singla said, "We are taking all precautionary measures with the assistance of high-tech security forces."

According to top police officials, the capital city was on the list of a possible Al Qaeda [Images] strike. There were also reports that suicide bombers, belonging to Bangladesh-based terrorist organisations, had sneaked into the state.

The IB had also alerted the state police to look out for suspicious Liberation Tigers of Tamil Eelam activities in the state.