An Indian soldier peers across the border into Pakistan in Singh Pura, about 22 miles from Jammu, India. (Channi Anand/AP)

India’s military remained on high alert and villagers fled border areas Friday, a day after a claimed commando-style mission against suspected militants in Pakistan-controlled territory — an operation that could signal a key shift in India’s longtime policy of restraint toward its regional rival.

Details remained scarce about the “surgical strike” that Indian paramilitary forces say they conducted Thursday against militants assembled in six “staging areas” just across the “line of control” dividing Kashmir.

India had said the counterterrorism strike killed militants in the “double digits.” Pakistan, meanwhile, said Indian forces did not cross the line and instead shelled border posts, killing two Pakistani soldiers.

The action came just days after alleged Pakistan militants crossed the border near the Indian town of Uri and killed 18 Indian soldiers at an encampment, with another soldier succumbing to his wounds Friday.

The two countries have fought over the disputed Kashmir Valley region for nearly 70 years, and it remains at the heart of the conflict between South Asia’s two nuclear-armed powers.

[Border zones often on edge]

Thursday’s claimed mission against militants was greeted with excitement in India, where fireworks crackled and the country awoke to banner headlines that read “India Strikes” and simply “PAYBACK.”

In Pakistan, meanwhile, officials continued to deny any cross-border operation took place and the local media turned quickly from that news to the latest on cricket star-turned-politician Imran Khan’s tour of Lahore.

Pakistan’s army chief, Gen. Raheel Sharif, toured a combat-readiness outpost in Lahore on Friday and said the military was in its “highest state of vigilance” along its border with India, one of the most heavily militarized in the world.

“Any misadventure by our adversaries will meet the most befitting response,” Sharif said.

Diplomats and analysts on both sides of the border said India’s actions could mark a new era in the showdowns between the two nations.

[Watch: India presses complaints at U.N. gathering]

India long embraced a policy of strategic restraint in its dealing with Pakistan and chose verbal warnings over military action — even after the country was hit by Pakistani-based terrorist groups, according to Lalit Mansingh, a former Indian foreign secretary and ambassador to the United States. This includes the terrorist siege on Mumbai in 2008 by Lashkar-e-Taiba that left more than 160 civilians dead.

“It definitely is a change in our relations with Pakistan. After the 1998 nuclear tests, there was a feeling that military retaliation would invite escalation. In most cases, verbal warnings were used,” Mansingh said, referring to the atomic tests by both nations amid spiking tensions.

“Now the government has sent a very muscular message to Pakistan: Every terrorist act will invite a retaliation in military and nonmilitary terms,” he added. “The restraint period is over.”

Experts have said Indian Prime Minister Narendra Modi — who rose to power on his reputation as a strong, nationalist leader — was under extreme pressure to respond forcefully to the terrorist strike at Uri and an earlier attack this year at a military encampment that left Indian six soldiers dead.

“India under Modi is a more assertive nation,” said Ram Madhav, the national general secretary for Modi’s Bharatiya Janata Party. “For it, the alternative to war is peace, but not terrorism and humiliation. ‘Zero tolerance to terrorism’ is the stated policy of our government.”

[Pakistan’s military boosts readiness]

The Indian government is also revisiting the terms of a water treaty between the two countries, reexamining their trade relationship and drumming up both international and regional diplomatic support.

Some experts in Pakistan suggested India’s strike was a ploy to detract attention to the worsening security in the Kashmir Valley, riven by deadly protests since July.

Others said the limited scale of this week’s clashes may prevent hostilities from escalating in the future.

“The Indian military was wiser and didn’t go for a deeper strike. They just fulfilled the wishes of the political leadership without causing any major disaster,” said Maj. Gen. Mahmud Ali Durrani, a former Pakistani ambassador to the United States. “Only two people died, and in the Indo-Pak context, two people dying on the border is almost routine.”

When reminded that the Indian government has said the casualties were in “double digits,” Durrani said: “We say two were killed and they will say 100. The truth is lost between India and Pakistan when the first bullet is fired.”

Shaiq Hussain in Islamabad and Rama Lakshmi in New Delhi contributed to this report.

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