New Delhi, Feb 1 (Agencies): Emphasising that India remains "vulnerable" to terrorism, Union Home Minister P Chidambaram on Tuesday said new groups are suspected to be responsible for some terror attacks that took place in recent years.

"I must caution you that there is no let up in the attempts to infiltrate into India from across the India-Pakistan border. Besides, there are a number of modules operating within the country and new groups have raised their heads that are suspected to be behind some terrorist attacks that took place in recent years," he said in his address at the 'Meeting of Chief Minister on Internal Security' here.

The Minister further said, "We cannot shy away from naming these groups or exposing their designs. Whatever their religious affiliations, I have no hesitation in condemning every group that resorts to terror as a means of advancing dubious religious causes or fundamentalist goals.

"Our policy in this regard is clear -- every terrorist and every terrorist group will be pursued and brought before the law and punished," he said.

Chidambaram, however, did not reveal the names any of the groups that were suspected to be behind some of the terrorists attacks in the last few years.

He said, "The evidence that the NIA and CBI are discovering every day should serve as a wake-up call to the new sources of terror that threaten our security."

On the challenge of Naxalism, the Home Minister said, "Looking back at 2010, my assessment is that there is a kind of a stalemate. The state governments concerned cannot claim any major advance, nor should we conclude that the CPI (Maoist) has gained the upper hand. There have been casualties on both sides."

Security forces had got serious setbacks last year including the loss of 75 CRPF personnel in one single attack by the Naxals in Dantewada district of Chhattisgarh.

The Minister said the CPI (Maoist) remains a powerful and determined enemy and has added at least four companies to the People's Liberation Guerrilla Army (PLGA), the armed wing of the Naxals.

Taking a dig at civil society activists, Chidambaram said in 2010, left-wing extremists killed 718 civilians of which 323 were killed after branding them as 'police informers'.

"Unlike our security forces, the Naxalite cadres are not constrained by the rule of law or rules of conflict. In areas they dominate they act as judge, jury and executioner.

"I regret that no representative of civil society has called for an inquiry into the brutal and unlawful killing of civilians and other acts of depredation committed by the CPI
(Maoist)," he said.