"The incident occurred in a house in Warsak village, Lal Pur district, on Tuesday when explosive remnants of war (ERW) exploded," Basir Zabuli from provincial police directorate told Xinhua.

According to the source, one of the victims found and brought the ERW after they returned collecting firewood from nearby mountains, in an effort to sell the item as scrap metals in the village.

Afghan officials use the term ERW referring to unexploded ordnance (UXO) and abandoned explosive ordnance (AXO).

Landmines, anti-personnel mines as well as ERWs left behind from wars kill or maim about 120 people every month in the post-conflict country, according to Afghanistan's State Ministry for Disaster Management.

On Monday, at least six children and a vendor were killed and several others wounded when an ERW exploded outside a school in remote Lal Pur district, near the border with Pakistan.