India has accused Pakistan of an “unprovoked act of aggression” after both countries claimed to have shot down each other’s military jets.
Islamabad captured an Indian pilot a day after Indian warplanes struck inside Pakistan for the first time since a 1971 war.
Tension has been running high since a suicide car bombing by Pakistan-based militants in Indian-controlled Kashmir killed at least 40 Indian paramilitary police earlier this month.
But the risk of conflict rose dramatically on Tuesday when India launched an air strike on what it said was a militant training base.
New Delhi claimed at least 300 militants were killed in Tuesday’s strike, while Pakistan says no one was killed.
The White House condemned the intensifying conflict and urged “both sides to take immediate steps to de-escalate the situation”.
Pakistan’s envoy to the United States, Asad Majeed Khan, said Islamabad would like to see the Trump administration play a more active role in easing the crisis. “We would certainly like to have more, and would certainly like to see more active involvement of the United States,” he told reporters.
At the same time, he said the lack of US condemnation of India’s strike on Pakistan is “construed and understood as an endorsement of the Indian position, and that is what emboldened them even more.”
Pakistani prime minister Imran Khan called for talks with India and hoped “better sense” would prevail so that both sides could de-escalate.
“History tells us that wars are full of miscalculation. My question is that, given the weapons we have, can we afford miscalculation,” Mr Khan said during a brief televised broadcast to the nation. “We should sit down and talk.”
The Pakistan government’s official Twitter account released a video of a man it claimed was an Indian pilot who had been shot down.
The man, whom Pakistan has named as Wing Commander Abhi Nandan and whose face was bloodied and blindfolded, gives his name and service number before telling a man questioning him: “I’m sorry sir, that’s all I’m supposed to tell you.”
A statement from India’s foreign ministry said the pilot’s treatment was a “vulgar display of an injured personnel of the Indian Air Force in violation of all norms of international humanitarian law and the Geneva Convention,” ordering his immediate release. India has not yet named the pilot.
Pakistan and India have fought three wars since independence from British colonial rule in 1947, two over the disputed Himalayan region of Kashmir, and went to the brink of a fourth in 2002 after a Pakistani militant attack on India’s parliament.
The latest escalation marks a sudden turnaround in relations between the two countries, both of which claim Kashmir in full, but only rule in part.
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Pakistan had said it had "no choice" but to respond to India's attack on its territory but did not want to escalate the crisis and avoided hitting military targets or causing casualties in an air strike, the main military spokesman said.
Major General Asif Ghafoor, head of the military press wing, said Pakistani jets had locked on to six targets in a demonstration of their capacity to hit key installations but had deliberately avoided causing any damage.
"We engaged a nearby open space where there were no humans or military installation," he told a news conference in Islamabad.
Taliban spokesman Zabiullah Mujahid said on Wednesday the group has not issued any press statement about the ongoing clashes between India and Pakistan.
Mujahid told Reuters that "the statement circulating about their comments on India, Pakistan clashes was fake".
We have not said that India, Pakistan clashes will affect the Afghan peace process. The press statement shared on social media and with news companies is fake."
The Press Trust of India news agency says these airports are located at Srinagar, Jammu and Leh. Indian authorities declined to comment.
He said they were "are being treated well" but made no mention of whether they would be returned to India.
A video has been released which is reportedly from the Pakistani government, which apparently shows one of the Indian pilots who has been captured.
The man, whose face is bloodied and blindfolded, gives his name and service number, before telling a man questioning him: "I'm sorry sir, that's all I'm supposed to tell you."

Analysis: How will Indian voters respond to Pakistan airstrikes?
The IndependentAnalysts say airstrikes clearly motivated by ‘intolerable’ bombing in Kashmir earlier this month – but rising anti-Pakistan sentiment can only help Modi’s BJP at the pollsPlease allow a moment for the liveblog to load