Al-Qaeda terrorists could be present in or around Delhi along with those of various other Pakistan-backed terrorist groups to disrupt Republic Day celebrations or target Deputy Prime Minister Lal Kishenchand Advani and some other prominent leaders, police said on Friday.

The terrorists, who could launch an aerial attack using a microlight plane, might also target the Indira Gandhi International Airport, the Delhi Metro Rail, the Red Fort or public places, Special Commissioner of Delhi police (Security) S K Kain said citing intelligence inputs.

The terror modules could include female suicide squads, he said.

Kain said that the networking of groups like the Lashkar-e-Tayiba, Jaish-e-Mohammed and Al Badr with some Sikh outfits like the Khalistan Commando Force and the Khalistan Zindabad Force had added a new dimension to the threats.

"The intelligence reports have warned of a renewed determination among the Pakistan-backed groups to carry out some sensational action on Republic Day," Kain said, adding that the police and other security agencies had made foolproof arrangements to thwart any such bid.