Security sources in Pakistan said the strikes overnight involved air and ground strikes against Taliban posts, headquarters and ammunition depots in multiple sectors along the border.
Both sides reported heavy losses, issuing sharply differing figures that Reuters could not independently verify.
"Our cup of patience has overflowed. Now it is open war between us and you (Afghanistan)," Pakistani Defence Minister Khawaja Muhammad Asif said on Friday.
The strikes threaten a protracted conflict along the 2600km frontier after a long-running dispute over Islamabad's accusation that Kabul harbours militants carrying out attacks inside Pakistan.
The Taliban have denied the charge and said Pakistan's security is an internal problem.
Taliban spokesman Zabihullah Mujahid said Pakistani forces carried out air strikes in parts of Kabul, Kandahar and Paktia.
Video shared by Pakistani security officials showed flashes of light in the night from firing along the border and the sound of heavy artillery.
A video of strikes on Kabul showed thick plumes of black smoke rising from two sites and a massive blaze in part of the capital Kabul.
Another video showed a building on fire, which the officials said was a Taliban headquarters in Paktia province.
"Pakistani counter-strikes against targets in Afghanistan continue," a Pakistani government spokesperson, Mosharraf Zaidi, said in a post on X, describing the action as a response to "unprovoked Afghan attacks".
Reuters witnesses in Kabul said many ambulance sirens could be heard following loud blasts and the sound of jets.
Zaidi said 133 Afghan Taliban fighters were killed and more than 200 wounded, with 27 posts destroyed and nine captured.
Mujahid, the Taliban spokesperson, said 55 Pakistani soldiers were killed and 19 posts seized, while eight Taliban fighters were killed, 11 wounded and 13 civilians injured in Nangarhar province.
Pakistan has been on high security alert since it launched air strikes earlier this week that Islamabad said targeted camps of Tehreek-e-Taliban, or Pakistani Taliban, and Islamic State militants in eastern Afghanistan.
Kabul said the strikes killed 13 civilians and reiterated it did not allow militants to operate from its territory.
The Taliban also warned there would be a strong response.
A state-run media outlet from Afghanistan's Nangarhar, Bakhtar News Agency, shared an image of what it said was a battalion of suicide attackers, and quoted an Afghan security source as saying the bombers were equipped with explosive vests and car bombs and were prepared to strike major targets.
Pakistani officials have said in recent days they feared an escalation of militant strikes in urban centres.
Clashes erupted along the frontier on Thursday night after the Taliban launched what it described as retaliatory attacks on Pakistani military installations.
Both sides had claimed to destroy border posts in that fighting.
with AP
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