UN officials in Afghanistan say that an investigation is under way into reports of more fighting between rival factions of the Hezb-e-Wahdat group in the north of the country.
A United Nations spokesman said the violence appeared to be centred on the Balkab district of Sari-e-Pul province.
A team of mediators had gone there from the northern provincial capital, Mazhar-e-Sharif.
The spokesman said that at least 66 people had been killed in factional fighting in the last two months.
Earlier this month an Afghan peace committee with UN participation managed to broker a fragile ceasefire between the rival Jamiat and Jumbesh factions in northern Afghanistan.
From the newsroom of the BBC World Service