KANDAHAR, Afghanistan (AFP) - Afghan soldiers were responsible for firing mortars at a wedding party that killed 17 women and children, officials said Friday, in a mistaken strike that overshadowed the transfer of nationwide security from NATO forces.
The deaths on Wednesday evening in the southern province of Helmand came on the eve of a ceremony in Kabul when President Ashraf Ghani congratulated the Afghan army and police for taking over from NATO forces who have ended their combat mission.
"The troops fired mortar rounds on a wedding ceremony after the militants in the same area attacked an army checkpoint," Mohammad Jan Rasoulyar, deputy governor of Helmand, told AFP.
"Those Afghan army troops accused of firing the mortar rounds have been referred to a military court." Four soldiers, including one commander, were arrested and taken to the provincial capital Lashkar Gah.
Officials said that a delegation sent to restive Sangin district in Helmand, where the incident took place, had been told that at least two rockets were fired at the wedding ceremony from different army outposts.
Some witnesses said the army attack was triggered when wedding guests shot celebratory gunfire into the air as the bride was brought to the groom's house.
A room where female guests had gathered was hit, with 17 women and children killed and 49 other people wounded. Officials had earlier reported the mortars killed at least 20 guests, but Rasoulyar said the toll had been revised down.
"Eyewitnesses told the delegation that militants had earlier attacked a security checkpoint in the area," Helmand police spokesman Farid Obaid told AFP.
"Then the Afghan army troops attacked with mortar rounds that landed on the wedding ceremony."
The UN mission condemned the attack, in which it said a house "was hit by at least one of three mortars fired from an Afghan National Army check-post".
President Ghani expressed his condolences for the "tragic incident", and said investigators would discover how the deaths had occurred.
The defence ministry said it was awaiting the delegation's official report.
The Taleban had issued a statement on Thursday saying the Afghan army was responsible.
The insurgent group has claimed the end of NATO's combat mission marks the defeat of US-led forces, which have been fighting since 2001, adding that no peace talks could happen before all foreign troops leave the country.
About 17,000 foreign soldiers, most of them from the US, will still be deployed in Afghanistan this year.
The United Nations said civilian casualties hit a new high in Afghanistan last year with about 10,000 non-combatants killed or wounded - 75 percent of them by the Taleban.