Indian leaders blamed Pakistan-based militant groups for an attack on a military base in Indian-administered Kashmir that left 17 soldiers dead and more than 20 injured on Sunday.
The four militants who attempted to storm the army base in the town of Uri were killed in a gunbattle, an army spokesman said.
The base is located near the Line of Control, a military frontier that divides the disputed Kashmir region into two parts, one administered by India and the other by Pakistan.
The attackers were suspected to be part of a fidayeen, or suicide squad, that infiltrated across the Line of Control from Pakistan-administered Kashmir and reached the base through a small water canal, military sources in Srinagar said.
Initial intelligence reports suggested they belonged to the Pakistan-based Islamist militant group Jaish-e-Mohammad, lieutenant general Ranbir Singh said at a press briefing in New Delhi.
The militants were all foreigners and some of the items they carried bore Pakistani markings, Singh said. They were heavily armed and carried automatic rifles, under barrel grenade launchers and other equipment.
Prime Minister Narendra Modi said those behind the attack would not go unpunished while Home Minister Rajnath Singh called Pakistan a terrorist state on Twitter.
"There are definite and conclusive indications that the perpetrators of Uri attack were highly trained, heavily armed and specially equipped," Singh said in a series of tweets.
"Pakistan is a terrorist state and it should be identified and isolated as such."
"I am deeply disappointed with Pakistan's continued and direct support to terrorism and terrorist groups," said Singh, who cancelled a trip to Russia and the US that was due to begin Monday.
The militants struck at dawn, breaching the fence of the base, and lobbed grenades and fired automatic weapons.
A large number of troops were stationed at the base, with a battalion that had returned from field duties handing over to another one.
The troops were quartered in temporary tents and shelters that caught fire during the attack, resulting in heavy casualties, the army said.
"Thirteen to 14 casualties of the 17 [soldiers] killed were primarily because of tents and temporary shelter catching fire," lieutenant general Ranbir Singh said. He said the combing operations in the area were still on.
Singh, who is the director general of military operations, said he had spoken to his Pakistan counterpart to express his concern and informed him of details of the recoveries from the slain militants and the country of their origin.
Twelve seriously injured soldiers had been airlifted to Srinagar, the capital of India’s Jammu and Kashmir state. The injured had both burn and bullet injuries. Four of them were in critical condition, NDTV news channel reported.
Army Chief Dalbir Singh had reached Uri for an on-the-ground assessment, an army spokesman said. Defence Minister Manohar Parrikar was holding consultations in Srinagar.
Nuclear-capable neighbours India and Pakistan have fought three wars and two of them have been over the disputed Kashmir region.
The latest attack has evoked a strong response from Indian politicians demanding what several termed “an effective response.”
"Days of so-called strategic restraint are over,” the ruling Bharatiya Janata Party’s general secretary in charge of Kashmir Ram Madhav posted on Facebook.
The opposition Indian National Congress party spokesman Jitendra Singh said it was time the Modi government sent a hard-hitting message to Pakistan.
“The attack seems to be aimed at triggering fresh violence and creating a war-like situation in the region,” Jammu and Kashmir Chief Minister Mehbooba Mufti said.
India-administered Kashmir has seen a violent secessionist movement since the 1980s. India blames Pakistan for aiding and abetting Kashmiri militants, a charge Islamabad denies, calling them freedom fighters.
More than 45,000 people – civilians, militants and security forces personnel - have been killed in Kashmir since the militant movement took hold in the 1980s.
India-administered Kashmir has seen a wave of violent protests in recent months over the killing of a young militant on July 8 which has led to the death of over 70 people in clashes with police and security forces and days of curfew-like restrictions.
The latest militant attack is likely to lead to continued curfew and heightened security in the region.
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Seventeen soldiers and four assailants were killed Sunday in an attack by suspected militants on an army base in Indian-administered Kashmir, the Indian Army said.