Security was tightened at airports across India on Sunday following a warning from the FBI that a plane flying to the United States or Europe could be hijacked, officials and television channels said. Passengers were frisked, baggage checked repeatedly and airport complexes barricaded after the FBI told Indian intelligence agencies that it had found an e-mail which spoke of plans to hijack a plane from India, the CNN-IBN television said. The television report did not clarify who sent the e-mail or if it had mentioned the name of any particular Indian airport. "This new alert has only led to a further stepping up of security measures," Dinesh Kumar, director of Chennai airport, told Reuters.