Imran Khan had asked the armed forces and the people of Pakistan to be prepared for "all eventualities."

Highlights Prime Minister Narendra Modi is meeting with top officials

Amid rising tension, many airports in north India shut down

Pakistan has also stopped flights from Islamabad and Lahore

In an escalation of hostilities a day after Indian Air Force Jets crossed the Line of Control and struck a terror training camp, Pakistan claimed "strikes across Line of Control from within Pakistani airspace".

There were reports of Pakistani fighter jets violating Indian air space in Jammu and Kashmir's Poonch and Rajouri sectors. A Pakistani F-16 aircraft crashed on its territory, in the Lam Valley area along the Line of Control.

Prime Minister Narendra Modi left an event early and met with top officials including National Security Advisor Ajit Doval, the Defence and Foreign Secretaries and intelligence officials.

Amid rising tension, India will avoid the Pakistani airspace, said officials. Eight airports in north India, including Amritsar, Chandigarh, Dehradun, Jammu, Srinagar and Leh, were declared shut by the Airports Authority of India, but the order was withdrawn within hours.

Pakistan has stopped flights from Islamabad and Lahore.

The area near the Line of Control has been on high alert amid warnings of retaliation by Islamabad after India's fighter jets destroyed a terror camp of the Jaish-e-Mohammed in Balakot, around 80 km from the Line of Control.

India said it was a "non-military and pre-emptive" strike based on credible inputs that Jaish was training suicide bombers for more attacks like Pulwama. Over 40 soldiers were killed on February 14 when a Jaish-e-Mohammed suicide bomber attacked a security convoy.

In a press release titled "Pakistani Strikes Back", Islamabad said on its strike claim: "This was not retaliation to continued Indian belligerence. Pakistan has therefore, taken strikes at non-military target, avoiding human loss and collateral damage. Sole purpose being to demonstrate our right, will and capability for self defence. We have no intention of escalation, but are fully prepared to do so if forced into that paradigm. That is why we undertook the action with clear warning and in broad daylight."

Amid the worst escalation between the two countries in decades, several countries have urged restraint.

This morning, Foreign Minister Sushma Swaraj said during a trilateral meeting in China that India wants to avoid any "further escalation of the situation".

"The limited objective of that pre-emptive strike was to act decisively against the terrorist infrastructure of Jaish-e-Mohammed in order to pre-empt another terror attack in India,"

Sushma Swaraj said in Wuzhen. "India does not wish to see further escalation of this situation. India will continue to act with responsibility and restraint," she stated.