At least seven people, including five schoolchildren, have been killed and 23 injured in a bombing near a girls’ school in southwestern Pakistan, officials said.

Friday’s attack targeted police guarding a polio vaccination drive in Mastung, a town in Balochistan province.

“The target was a police van which was going to pick up a polio [vaccination] team,” Senior Superintendent of Police Rahmat Ullah told the Reuters news agency.

One police officer and a shopkeeper were also killed in the explosion, senior police officer Abdul Fatah told the AFP news agency.

The blast was believed to have been caused by an improvised device attached to a motorcycle parked near the school.

No group has claimed responsibility for the attack. But Islamabad has frequently blamed the Taliban government in neighbouring Afghanistan for failing to root out attacks on Pakistan from across the border.

Prime Minister Shehbaz Sharif condemned the attack.

Interior Minister Mohsin Naqvi said “targeting children is an act of brutality”.

On Tuesday, a policeman was killed in an attack on a health office that manages door-to-door polio vaccination campaigns.

The attacks have coincided with Pakistan’s third nationwide polio campaign, which was launched on Monday amid a significant rise in cases of the viral disease.

It aims to vaccinate 45 million children under five across 71 districts and comes in response to 41 polio cases reported predominantly in the provinces of Balochistan and Sindh.

Polio cases had dropped in 2023 to six, from 20 in 2022. Pakistan and Afghanistan remain the only countries where polio is endemic.

Armed groups have previously targeted polio teams, spreading false conspiracy theories that the vaccinations are part of a Western sterilisation programme.

Pakistan is facing a surge in deadly attacks in its northwest and a growing separatist movement in the south.

The most active group in Balochistan is the Balochistan Liberation Army (BLA), a separatist group that regularly targets Islamabad’s security forces and citizens hailing from elsewhere in Pakistan.

Health workers mark locations as they administer polio vaccines to children during a door-to-door vaccination campaign in Karachi, Pakistan, on October 31, 2024 [Shahzaib Akber/EPA-EFE]