KABUL - A blast tore though a religious school during prayer time in the northern Afghan province of Samangan on Wednesday, killing 15 people, a provincial spokesperson said.

At least 20 people were also wounded in the explosion in the provincial capital of Aybak, Emdadullah Muhajir, spokesperson for Samangan's provincial government added.

"A blast took place around 12:45pm inside Jahdia Madrassa in the centre of city. Lots of boys are studying at this madrassa (religious school)," he said.

It was not immediately clear who was behind the blast. Muhajir said an investigation had begun.

Interior ministry spokesperson Abdul Nafi Takor confirmed the blast but put the death toll so far at 10 with more injured.

"Our detective and security forces are working to identify the perpetrators of this unforgivable crime and bring them to justice," Takor said.

The Taliban say they are focused on securing the war-torn nation since taking over the country last year, however several attacks, including at mosques, have taken place in recent months, some of which have been claimed by the Islamic State.

(Reporting by Mohammad Yunus Yawar; Writing by Charlotte Greenfield; Editing by Frank Jack Daniel and Andrew Heavens)