Unidentified armed men set ablaze a middle school in Afghanistan's eastern Paktika province, an official said Saturday.

"Unknown gunmen entered Zarabi, a joint boy and girl middle school and set ablaze the building along with all materials and equipment in Urgun district at around 2 p.m. local time Saturday," Mohammad Nasim Wajid, provincial deputy education director, told Xinhua.

All documents, books and furniture have been burnt as the fire engulfed the school building, said the official.

Over 900 students including 400 girls have been studying in the school, said the official.

No group has claimed responsibility for the incident so far.

More than 9.5 million Afghan children with around 40 percent of them girls attend 15,000 schools across the country, while over 3.5 million school age children have no access to education due to poverty, conflicts and insurgency, according to education officials.