An illegal ammunition dump in northern Afghanistan has exploded, killing at least 28 people and injuring scores of others. Officials say the arms belonged to an Afghan militia commander.

The Afghan government says the blast leveled an entire neighborhood in the village of Bashgah, 120 kilometers north of Kabul.

Interior Ministry Spokesman Latfullah Mashal says the weapons belonged to a militia commander who just weeks ago had officially been disarmed.

"But he still retained these shells and ammunition in an underground bunker close to his house," he said.

The dump contained mortar and artillery rounds and other ordnance.

Afghanistan is awash with old weapons after years of conflict. The government began a drive to disarm private armies in 2003, but much ordnance remains uncollected.

Mr. Mashal says an investigation into the exact cause of the deadly explosion is underway.

"So far we do not know if it was an accident or was it destructive action of the terrorist or what," he said.

Baghlan province, where the blast occurred, is not a stronghold for Taleban insurgents and Mr. Mashal says factional fighting between warlords is a possible cause.

Afghanistan has seen a number of explosions at arms depots in recent years, but this blast was the most deadly.