Pakistan security official at the border with Afghanistan on 18 February 2017

At least four people have been killed and several others wounded in an attack on a courthouse in north-west Pakistan, officials say.

Three suicide bombers were killed after they tried to enter the court in the Tangi area of Charsadda district, local media quote officials as saying.

Explosions and gunfire could be heard.

The Pakistani Taliban group Jamaat-ur-Ahrar says it carried out the attack, the latest in a number of bombings to hit the country in recent days.

Spokesman Asad Mansoor said fighting was still continuing in the court, Reuters news agency reports.

The suicide attackers reportedly threw hand grenades and opened fire as they tried enter the court premises.

One bomber blew himself up and the others were killed, although one report said one attacker was still alive and on the loose inside the court complex.

At least one lawyer is reported to be among four dead. A witness told Reuters he had seen “many” dead bodies.

“I escaped towards the canteen and climbed the wall to save my life,” said local resident Mohammad Shah Baz. “But there were many people dead and injured”.

Pakistan has been hit by a wave of suicide bomb attacks claimed by various Islamist militant groups in recent days.

At least 80 people were killed when a suicide bomber blew himself up at a shrine in the southern town of Sehwan last week in an attack claimed by the so-called Islamic State (IS).

In response, Pakistan launched a security crackdown – which included closing border crossings with Afghanistan – and claims it killed 100 militants.