Pakistan bombed Afghanistan’s capital of Kabul and two other provinces on Friday, hours after a cross-border attack, the latest escalation of violence between the volatile neighbours who last year signed a Qatar-mediated ceasefire.

Following months of tit-for-tat clashes, Afghan forces attacked Pakistani border troops on Thursday night in what the Taliban government said was retaliation for earlier deadly air strikes.

Hours later, at least three explosions were heard in Kabul on Friday morning, but there was no immediate information on the exact location of the strikes in the Afghan capital, or of any potential casualties.

Relations between the neighbours have plunged in recent months, with land border crossings largely shut since deadly fighting in October that killed more than 70 people on both sides.

Islamabad accuses Afghanistan of failing to act against militant groups that carry out attacks in Pakistan, which the Taliban government denies.

The UN secretary-general, António Guterres, urges both sides to protect civilians as required under international law and “to continue to seek to resolve any differences through diplomacy,” UN spokesperson Stephane Dujarric said.

Commenting on the Friday airstrikes, Pakistan’s interior minister Mohsin Naqvi said the strikes on Afghanistan were a “befitting response”.

“Pakistan’s armed forces have given a befitting response to the Afghan Taliban’s open aggression,” said Naqvi.

Government spokesperson Zabihullah Mujahid said Pakistan also carried out airstrikes in Kandahar to the south and in the south-eastern province of Pakistan.

Afghanistan said its military launched its attack across the border into Pakistan late on Thursday in retaliation for deadly Pakistani airstrikes on Afghan border areas on Sunday, and claimed to have captured more than a dozen Pakistani army posts.

Efforts to produce a lasting agreement between the two nations had failed, with negotiations and an initial ceasefire brokered by Qatar and Turkey in October looking increasingly shaky.

Afghanistan’s defence ministry said 55 Pakistani soldiers had been killed in the attack on Thursday, including some whose bodies had been taken into Afghanistan, while “several others were captured alive”. It put its own casualties at eight killed and another 11 wounded.

The Pakistan information minister, Attaullah Tarar, however, said the number of Pakistani soldiers killed stood at two, with three wounded. He said 36 Afghan fighters had been reported killed.

Mosharraf Ali Zaidi, spokesperson for Pakistan’s prime minister Shehbaz Sharif, denied that any Pakistani soldiers had been captured.

Pakistan and Afghanistan share a 2,611km-long border known as the Durand Line, which Afghanistan has not formally recognised.

Afghan authorities were evacuating a refugee camp near the Torkham border crossing after several refugees were wounded and 13 civilians, including women and children, killed, authorities said.

On the Pakistani side of the border, local police said residents were also evacuating to safer areas, while some Afghan refugees who had been waiting to cross back into Afghanistan were also moved to secure locations. .

Tension has been high between the two neighbours for months, with deadly border clashes in October killing dozens of soldiers, civilians and suspected militants. The violence followed explosions in Kabul that Afghan officials blamed on Pakistan. Islamabad, at the time, conducted strikes deep inside Afghanistan to target militant hideouts.