A Taliban assault on a police checkpoint led to the deaths of four students Saturday in eastern Ghazni province, a provincial official said.

Arif Noori, a spokesman for provincial governor, said that 17 others, including 15 students and two teachers, were wounded when an explosion, likely caused by rocket fire, hit the school in Andar district.

The spokesman added that the students killed are between 10 and 16 years old.

He said that provincial officials are investigating who fired the projectile hitting the school during the standoff between security forces and Taliban.

No one immediately claimed responsibility for the attack.

Taliban insurgents have stepped up their attacks against Afghan security targets in recent months.

In a separate incident in northeastern Badakhshan province, Taliban insurgents overran a district headquarters late Friday, said Nek Mohammad Nazari, a spokesman for the provincial governor.

"Afghan security forces retreated from the Arghanj Khowa district headquarters to avoid civilian causalities," said Nazari. Reinforcements have been dispatched to repel the Taliban, he added.

The Taliban assault began Thursday night, killing four police and wounding five others, according to officials.

Zabihullah Mujahid, a spokesman for the Taliban, claimed the attack. Mujahid said that their fighters were able to seize large amounts of ammunition and weapons, as well as two military vehicles.

Badakhshan province has 28 districts, and at least two other districts, Wardoj and Yamgan, are already under the Taliban's control.