Afghan officials say an accidental explosion killed four insurgents and a civilian near a sporting event in an area controlled by the Taliban.
Maj. Hanif Rezaie, an army spokesman, says one of the fighters killed in the northern Baghlan province was a local commander.
A provincial official says another 20 people, including Taliban fighters and civilians who had gathered to watch a volleyball match, were wounded.
The official spoke on condition of anonymity because he was not authorised to speak to the media.
Elsewhere in Afghanistan, a female university student was killed when a sticky bomb attached to a vehicle was detonated, according to the office of the provincial governor of Nangarhar province.
The Taliban hold sway over nearly half of Afghanistan.