In a major incident, Prime Minister Atal Bihari Vajpayee's security was breached in Delhi late on Tuesday night while he was traveling from the airport to his official residence.

A white Esteem car (HR 26 Q 0427) intruded into a sanitised road at a red light on the Rao Tularam Marg in south Delhi around midnight and attempted to overtake the prime minister's vehicle although all traffic had been stopped.

The Special Protection Group personnel escorting the prime minister fired at the erring vehicle, which reportedly had three occupants, but it managed to disappear.

An alert has been sounded across Delhi and a massive hunt launched to track down the car.

Police in the neighbouring districts of Gurgaon and Faridabad in Haryana and Ghaziabad in Uttar Pradesh have also been alerted.

Senior officials of the Delhi Police, Intelligence Bureau and the SPG held a late night meeting in view of the sensational incident.

The prime minister was returning after a day-long visit to Mumbai when the incident occurred.

Intelligence agencies have been warning of threats to the prime minister from various terrorist groups and this is the second breach in the PM's security in the last 10 days.

Some days back, a Maruti van had hit the pilot car of the prime minister's motorcade and vanished taking advantage of the dense fog.