<!– /11440465/Dna_Article_Middle_300x250_BTF –>Security at international airports in Mumbai, Hyderabad and Chennai was put on maximum alert after the state police forces and the Central Industrial Security Force (CISF), which guards the airports, were informed about a possible aircraft hijack attempt.The security protocols at these airports have been increased to the level in place on the Republic Day and Independence Day.An airport security review meeting was also called at the Indira Gandhi International (IGI) airport where officers from the Bureau of Civil Aviation, Delhi Police, CISF and intelligence agencies participated.“The security has been upgraded in a grading manner. This means that with regard to the intensity of threats, security of different parts of the airport has been increased. Frisking has been stepped up too at the security hold area as well as at the secondary ladder point, before boarding. Armed men have been deployed to maintain a hawk-eye vigil inside the terminals and on the airside,” said a senior CISF officer.The alert was sounded after a Hyderabad-based woman sent an email to Mumbai Police saying that she had overheard six people in her city discussing their plan of hijacking planes simultaneously in Mumbai, Chennai and Hyderabad on Sunday. According to the sources in the security establishment in Mumbai, the woman claimed that 23 people were involved in the hijack plan and that they would work in groups and would board the flights from the three airports at a time.Following the alert, the Mumbai Police passed on the information to the CISF after which a high-level meeting was conducted on Saturday night and counter-terrorism measures were discussed at length.An officer from Sahar police station said, “We were informed about the threat and were told that an alert has been issued. We are taking all necessary measures. Security has been beefed up as per the standard procedure.”“We were told about the number of possible hijackers, their modus-operandi,” said a CISF official, requesting anonymity.He said anti-sabotage checks are being conducted at the airports and a close watch will be kept on suspicious elements. “Further course of action will be decided after Mumbai police verify the facts of the inputs and give us a compliance report.”“We are not taking any chances and have sounded an alert in the matter. We are also checking if the information was a hoax or not,” said another police officer.Just a fortnight ago Mumbai police had issued an advisory and had prohibited use of drone and other flying objects in the city after they suspected an aerial attack by anti-social elements.VENEZUELAN DETAINEDDehradun: A 27-year-old Venezuelan woman has been detained with a satellite phone at Jolly Grant airport here. Police officials said that the Army and Intelligence Bureau are investigating the case.