At least 50 civilians have been killed by militants in northern Afghanistan, officials say.

They report that a checkpoint manned by local police was attacked in the Mirzawalang area of Sar-e Pul province.

The assailants then entered the village and shot dead mainly Shia Muslim civilians including women and children, a spokesman for the provincial governor said.

"They were killed in a brutal, inhumane way," he added.

He reported that seven members of the Afghan security forces has also been killed, as well as a number of insurgents.

A combination of Taliban and Islamic State (IS) group fighters - including foreigners - were involved, he said. Both are Sunni Muslim militant groups.

The Taliban denied killing civilians, saying that its fighters had killed 28 members of a government-supported militia in the area.

Afghan President Ashraf Ghani condemned the attack.

"Criminal terrorists have once again killed civilians, women and children," he said in a statement.

"This barbaric act of them is deemed a direct violation of human rights and a war crime."

Read more:  BBC News