A suicide bomber killed more than 40 people, including five children, when he struck a mosque in northern Afghanistan after Eid al-Adha prayers on Friday, officials said.

It was the worst death toll in a single attack in Afghanistan since Dec 6 last year, when 80 died in a suicide blast at a shrine in Kabul on the Shiite holy day of Ashura.

At least 50 others were wounded as the bomb - reportedly stuffed with ball-bearings - ripped through the crowd of worshippers in Maymana city in Faryab province.