MUZAFARABAD, Pakistan (AP) — Pakistan's military said Wednesday it shot down two Indian warplanes in the disputed region of Kashmir and captured a pilot, raising tensions between the nuclear-armed rivals to a level unseen in the last two decades.

India acknowledged one of its air force planes was "lost" in skirmishes with Pakistan and that its pilot was "missing in action" on a chaotic day, which also saw mortar shells fired by Indian troops from across the frontier dividing the two sectors of Kashmir kill six civilians and wound several others. A helicopter crash in the region also killed six Indian air force officials and a civilian on the ground.

Pakistan responded by shutting down its civilian airspace as Prime Minister Imran Khan called for negotiations with his Indian counterpart Narendra Modi, to ensure "better sense can prevail."

"Let's sit together to talk to find a solution," Khan said. There was no immediate reaction from Modi.

The aircraft went down Wednesday morning in Kashmir, a mountainous region claimed by both India and Pakistan since almost immediately after their creation in 1947. One of the downed planes crashed in Pakistan's part of Kashmir while the other went down in Indian-controlled section of the Himalayan region, Pakistan's army spokesman Maj. Gen. Asif Ghafoor said.

Pakistani troops on the ground captured an Indian pilot, he later said, after earlier saying it captured two. He did not explain what caused the confusion.

The pilot was injured and was being treated at a military hospital, Ghafoor said. He did not elaborate beyond saying the pilots were being "treated well" and made no mention of them being returned to India.

"We have no intention of escalation, but are fully prepared to do so if forced into that paradigm," he added.

India's External Affairs Ministry spokesman Raveesh Kumar said one of its MiG-21 fighter aircraft was missing. He said India was still "ascertaining" whether its pilot was in Pakistan's custody. He said one Pakistani aircraft was shot down, something Pakistan denied.

Meanwhile, Indian police said officials recovered seven bodies from the wreckage of an Indian Air Force chopper that crashed in Indian-controlled sector of Kashmir, which included six Indian airmen and a civilian on the ground. They gave no cause for the crash.

Senior police officer Munir Ahmed Khan said the chopper crashed close to an airport on Wednesday in Budgam area, in the outskirts of the region's main city of Srinagar. The Srinagar airport, which has been shut along with two other airports for civilian flights in the region, is also an air force station.

Eyewitnesses said soldiers fired in air to keep residents away from the crash site.

Hours later, Pakistan's Civil Aviation Authority said it shut Pakistani airspace to all commercial flights on Wednesday, without elaborating or indicating when the flights might resume. It was not clear if the shutdown applied to commercial overflights, though aviation authorities in Bahrain and the United Arab Emirates stopped all flights to Pakistan.

Meanwhile, the Foreign Ministry in Islamabad said the country's air force was carrying out airstrikes Wednesday from within Pakistani airspace across the disputed Kashmir boundary but that this was not in "retaliation to continued Indian belligerence."

Ghafoor, the Pakistani military spokesman, said the strikes were aimed at "avoiding human loss and collateral damage."

The shelling earlier Wednesday by India hit the village of Kotli in Pakistani-controlled Kashmir, killing six people, including children, local police official Mohammad Altaf said.

Kashmir is split between Pakistan and India and claimed by both in its entirety. Though Pakistani and Indian troops in Kashmir often trade fire, the latest casualties came a day after tensions escalated sharply following a pre-dawn airstrike and incursion by India that New Delhi said targeted a terrorist training camp in northwestern Pakistan.

Tuesday's pre-dawn strike by India was its first inside of Pakistan since the two nations' 1971 war over territory that later became Bangladesh. Pakistan had said that Indian warplanes dropped bombs near the Pakistani town of Balakot but there were no casualties.

The violence Wednesday marked the most-serious escalation of the long-simmering conflict since 1999, when Pakistan's military sent a ground force into Indian-controlled Kashmir at Kargil. That year also saw an Indian fighter jet shoot down a Pakistani naval aircraft, killing all 16 on board.

Residents on both sides of the de-facto frontier, the so-called Line of Control, said there were exchanges of fire between the two sides through the night into Wednesday morning. Hundreds of villagers fled border towns in both India and Pakistan.

In New Delhi, Indian officials said Wednesday at least five of their soldiers were wounded in firing by Pakistani troops along the volatile frontier.

Lt. Col. Devender Anand, an Indian army spokesman, said Pakistani soldiers targeted dozens of Indian military positions across the Line of Control throughout the night. An Indian military statement said that "out of anger and frustration," Pakistan "initiated unprovoked cease-fire violation."

The statement said Indian troops "retaliated for effect" and claimed to have destroyed five Pakistani posts. It accused Pakistani soldiers of firing mortars and missiles "from civilian houses, using villagers as human shields."

On Wednesday, Pakistan's Foreign Minister Shah Mahmood Qureshi told state-run Pakistan Television he was in touch with his counterparts across the world about the "Indian aggression," adding that New Delhi had endangered peace in the region by Tuesday's airstrike on Pakistan.

India's External Affairs Minister Sushma Swaraj said Wednesday her country does not wish to see further escalation of the situation with Pakistan and that it will continue to act with responsibility and restraint.

She said the limited objective of India's pre-emptive strike inside Pakistan on a terrorist training camp Tuesday was to act decisively against the terrorist infrastructure of Jaish-e-Mohammad group, to pre-empt another terror attack in India.

The latest wave of tensions between Pakistan and India first erupted after the militant group Jaish-e-Mohammad claimed responsibility for the Feb. 14 suicide bombing of a convoy of India's paramilitary forces in the Indian portion of Kashmir that killed over 40 Indian troops.

Pakistan has said it was not involved in the attack and was ready to help New Delhi in the investigations. India long has accused Pakistan of cultivating such militant groups to attack it.

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