Pakistan carried out airstrikes early Friday in Afghanistan’s capital of Kabul as well as in Kandahar and Paktia provinces, according to Afghan government spokesman Zabihullah Mujahid, marking a sharp escalation in hostilities between the two neighboring countries. The strikes came just hours after Afghanistan said it launched a cross-border attack into Pakistan in retaliation for earlier Pakistani operations along the frontier.

Residents in Kabul reported hearing at least three explosions, though there was no immediate confirmation of casualties or the precise targets within the city. Two senior Pakistani security officials said their military struck what they described as Afghan military facilities in Kabul, Kandahar and Paktia, claiming two brigade bases were destroyed. They did not provide casualty figures.

Afghanistan’s Defense Ministry said its forces had initiated large-scale offensive operations late Thursday along the disputed 2,611-kilometer Durand Line, asserting that 55 Pakistani soldiers were killed and more than a dozen posts captured. Islamabad disputed those figures. Pakistan’s Information Minister Attaullah Tarar said two Pakistani soldiers were killed and three wounded, while claiming dozens of Afghan fighters died in the clashes. A spokesperson for Prime Minister Shehbaz Sharif denied that any Pakistani troops were captured.

Both sides also reported exchanges of fire near the Torkham border crossing. Afghan authorities said 13 civilians were wounded when a missile struck a refugee camp near Torkham, including women and children. On the Pakistani side, residents evacuated villages after mortars reportedly landed nearby, though police said there were no civilian casualties.

The latest confrontation has cast doubt on a ceasefire mediated by Qatar that had largely held despite sporadic border skirmishes. Tensions have remained high amid Pakistan’s campaign against militant groups it says operate from Afghan territory, including factions linked to the Pakistani Taliban. Kabul denies harboring such militants and has accused Islamabad of violating Afghan sovereignty with repeated airstrikes.

U.N. Secretary-General Antonio Guterres urged both countries to protect civilians and resolve differences through diplomacy, warning that further escalation could destabilize the broader region.