India on Alert

The alert comes in the wake of a terrorist attack on India's financial hub Mumbai last week that left more than 170 people dead.

An email to officials at the Delhi airport warned of hijacking and terror strikes from the Deccan Mujahedeen between Wednesday and Sunday, IANS news agency reported citing official sources.

The little-known organization had claimed responsibility for the Mumbai terror attacks.

An official of the Ministry for Civil Aviation said she was not aware of the mail or a hijack threat as reported by some news channels. "Security has been heightened on basis of intelligence inputs," Moushumi Chakravarty, an information officer at the ministry, said.

She said additional paramilitary and police personnel have been deployed at airports across India. Tightened security was also implemented at the Delhi, Bangalore and Chennai airports. International flights land at all three airports. "Passengers have been asked to arrive three hours before their flights. There is more detailed checking. All luggage is being 100 per cent checked."

She said more layers of security had been put in place. All vehicles entering the airport premises were being scrutinized and there was more "perimeter surveillance."

Mosque destruction anniversary signals high alert

There is usually a high alert at major government installations across India on December 6. On that day in 1992, Hindu fanatics pulled down the medieval Babri mosque in the northern city of Ayodhya.

The destruction of the mosque triggered nationwide sectarian riots in which more than 1,000 people were killed.

Chiefs of the Indian army, navy and air force held a meeting with federal Defense Minister AK Antony in New Delhi late Wednesday to review security issues.

Indian Air Force Chief Fali Homi Major confirmed on Thursday that the possibility of an aerial attack by terrorists had been discussed at the meeting, PTI news agency reported.

"This (security alert) is based on a warning which has been received by the government and we are prepared as usual," Major was quoted as saying by IANS, when asked about the possibility of air strikes by terrorists.

India has seen an increased surge of terrorist attacks in 2008, with serial bombings in several major cities, including the Rajasthan capital of Jaipur, Ahmedabad in Gujarat and Guwahati in the north- eastern state of Assam.

More than 400 people have been killed in these attacks.