Pakistan's defence minister has said that the country is in an "open war" with neighbouring Afghanistan, after both nations launched strikes overnight.
Khawaja Muhammad Asif said Islamabad's patience had run out as tensions escalated, with casualties reported on both sides.
"Our cup of patience has overflowed," he said in a social media post. "Now it is open war between us and you (Afghanistan)."
He alleged the Taliban had turned Afghanistan "into a colony of India", gathered militants from around the world and begun "exporting terrorism".
There has been no reaction from Afghan government officials to Mr Asif's comments.
Pakistan carried out strikes in the Afghan capital, Kabul, and two other Afghan provinces overnight, Afghanistan government spokesman Zabihullah Mujahid said, just hours after Afghanistan launched a cross-border attack on Pakistan.
Security sources in Pakistan said the strikes involved air and ground strikes against Taliban posts, headquarters and ammunition depots along the border.
A Reuters news agency witness in Kabul said many ambulance sirens could be heard following a series of loud blasts.
Both sides reported heavy losses, issuing sharply differing figures that have not been independently verified.
Afghanistan's Defense Ministry said overnight that 55 Pakistani soldiers had been killed, including some whose bodies were taken into Afghanistan, and that "several others were captured alive."
It said eight Afghan soldiers were killed and 11 wounded. The ministry said it destroyed 19 Pakistani army posts and two bases and that the fighting ended around midnight, about four hours after it began Thursday.
Pakistan's Information Minister Attaullah Tarar said two Pakistani soldiers were killed and three wounded.
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Mosharraf Ali Zaidi, a spokesperson for Pakistan's Prime Minister Shehbaz Sharif, denied that any Pakistani soldiers had been captured.
In a post on X, he said at least 133 Afghan fighters were killed and more than 200 wounded.
He also said 27 Afghan posts were destroyed and nine fighters captured.
He did not specify where the casualties occurred but said additional losses were estimated in strikes on military targets in Kabul, Paktia and Kandahar.
Cross-border battles have intensified following months of tensions and skirmishes between the two nations.
The escalation threatens a fragile ceasefire along the 1,615-mile border and deepens a dispute over Islamabad's claim that Kabul harbours Tehreek-e-Taliban Pakistan (TTP) militants - an accusation the Taliban deny.
(c) Sky News 2026: Pakistan in 'open war' with Afghanistan, Pakistani defence minister says
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