The civilians were killed because of a misunderstanding, said the spokesman, adding that an investigation of the incident was underway.

In a third incident, eight guards working for a private security company were killed in the explosion of a remote-controlled mine in the restive province of Helmand, the Afghan Interior Ministry said.

'A remote-control mine trapped two vehicles of Hamayoon Private Security Company. As a result, at least eight guards of the company were killed and four others were injured,' the statement said.

The ministry said the incident took place in the Yakhchal area of the province's Grishik district at 8 a.m.

No group had claimed responsibility for the attack, but the ministry said that the mine was planted by the 'enemies of Afghanistan'.