Indian army put on high alert

India put its army on high alert today as it decided how to respond to the terrorist attack on parliament, which it blames on Islamic militant groups backed by Pakistan.

Pakistan, meanwhile, asked New Delhi to end the ‘‘blame game’’.

The sharp exchanges between the nuclear-armed neighbours have taken a threatening tone after a suicide attack on the Indian parliament in New Delhi last Thursday in which five attackers and eight others were killed.

India has said the attackers were Pakistanis whose operation was planned by the country’s intelligence agency.

India is considering various forms of retaliation, including bombing the terrorist training camps it says are scattered across Pakistan.

Islamabad has warned of serious repercussions.

‘‘We are alert,’’ said Foreign Minister Jaswant Singh, when asked about an apparent Pakistani troop movement along the border.

Interior Minister Lal Krishna Advani suggested yesterday that India would be within its rights to send troops across the border to chase Islamic guerrillas.

‘‘If one country attacks its neighbour or sends its people to indulge in sabotage and killings, hot pursuit is regarded as a legitimate response,’’ he said.

New Delhi’s police commissioner said the confessions of three men and a woman, accomplices of the suicide squad, showed that the Pakistan-based Jaish-e-Mohammed and Lashkar-e-Tayyaba militant groups planned the parliament attack with the help of Pakistan intelligence (ISI).

The assault at the heart of the world’s largest democracy prompted angry calls from across the country, including the ruling party, to emulate the attacks by the United States against the Taliban and Osama bin Laden’s al-Qaida terrorist network in Afghanistan, and those by Israel against Palestinian installations.

Across the border in Pakistan, Information Secretary Anwar Mahmood said today that Pakistan would act on any ‘‘credible proof’’ that the Jaish-e-Mohammed was involved in the attack. But he said India must stop accusing Pakistan of complicity.

‘‘The blame game must end,’’ he said. ‘‘Pakistan expects India to look into the matter in a dispassionate manner, rather than blaming Pakistan and ISI for anything and everything.’’

Striking a note of caution, the Communist Party of India-Marxist today said a strike on Pakistani territory would ‘‘spark off full-scale war,’’ the Press Trust of India reported.

India accuses Pakistan of sponsoring and training the guerrillas; Pakistan counters that it backs the rebels only with ideology, not weapons.

The militants have waged a separatist movement since 1989 in Jammu-Kashmir state, in a campaign that has killed tens of thousands of people. They are seeking an independent Kashmir or merger with Muslim Pakistan.