Pakistan carried out overnight air strikes on major cities in Afghanistan.
Officials in Islamabad and Kabul confirmed the strikes on Friday.
The attacks mark a sharp escalation in months of border clashes between the neighbours.
Security sources said the strikes targeted locations linked to militant activity.
Afghan officials described the attacks as a violation of sovereignty.
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They said civilians were put at risk during the overnight operation.
Pakistan said the action followed repeated cross-border security incidents.
The latest development raises fears of wider instability in the region.
Diplomatic efforts to de-escalate tensions remain uncertain.
