New Delhi, Aug 17 - Emphasising that cross-border terrorism was still a major threat, Prime Minister Manmohan Singh Monday warned that the government had credible information of terror groups in Pakistan planning fresh attacks against India.

'Coming to specific challenges, cross-border terrorism remains a most pervasive threat. We have put in place additional measures after the Mumbai terrorist attack in November last year. But there is need for continued vigilance,' Manmohan Singh said at a meeting on internal security attended by chief ministers.

'There is credible information of ongoing plans of terrorist groups in Pakistan to carry out fresh attacks. The area of operation of these terrorists today extends far beyond the confines of Jammu and Kashmir and covers all parts of our country.'

Calling for a coordinated response by both the central government and the states, the prime minister said more needed to be done to shore up intelligence systems and speed up the response to terrorist attacks.

'A well-calibrated coastal security scheme is being put in place. But we obviously need to do much more and we shall,' he said.

'The challenges posed by asymmetric warfare and terrorism as also left wing extremism can only be met through new ideas and more resolute actions and determination. We need to be ahead of the curve if we are to succeed as we must.'

While mentioning that the overall security situation in Jammu and Kashmir had improved in the past few years, with violence steadily declining, Manmohan Singh also spoke of 'disturbing trends'.

'There are some disturbing trends on the horizon. Levels of infiltration which had come down very substantially have seen a surge this year, alongside an increase in attempts at infiltration. The infiltrators appear more battle-hardened, better equipped, and in possession of sophisticated communications.'

The prime minister, who addressed a similar conclave in January after the 26/11 terror strikes, said there were also signs of a revival of over-ground militant activities in the troubled state.

'Attempts are being made to link isolated and unconnected incidents -- such as those which occurred in Shopian, Sopore, Baramulla -- to create an impression of a ground swell of anti-national feeling.