A suicide bomber driving a three-wheeled vehicle packed with explosives attacked a police checkpoint in northwestern Pakistan on Tuesday, killing at least seven people and injuring about 20 others.

Police authorities said the attacker approached two traffic police officers stationed at the checkpoint before detonating the explosives, triggering a powerful blast that caused multiple casualties and widespread panic in the area.

Senior police official Muhammad Sajjad Khan said preliminary investigations indicated that the bomber deliberately targeted the checkpoint before carrying out the attack.

The incident comes only days after another deadly assault in Bannu, where a vehicle bomb exploded near a security checkpoint before armed militants opened fire on police officers, leaving at least 15 people dead.

Meanwhile, tensions between Pakistan and neighbouring Afghanistan continue to rise over accusations of cross-border militancy. Pakistan’s Foreign Ministry on Monday summoned Afghanistan’s top diplomat in Islamabad after claiming that a recent suicide attack had been orchestrated by militants operating from Afghan territory.

However, Afghanistan’s Taliban-led government has repeatedly rejected allegations that it provides sanctuary for militants targeting Pakistan.

Relations between both countries have deteriorated in recent months, with clashes along the border and Pakistani airstrikes on locations inside Afghanistan further deepening the crisis.