Kabul, Afghanistan (CNN) -- At least 14 civilians died when a mini-bus struck a road mine in southern Afghanistan on Thursday, a provincial official said.
The incident occurred in the Nahr-e-Saraj district in Helmand province, where fighting between militants and troops occurs frequently.
President Hamid Karzai swiftly condemned the incident.
Daud Ahmadi, the Helmand governor's spokesman, said four people were injured, and NATO's International Security Assistance Force said Afghan and international troops provided medical assistance and evacuated the wounded.
Women and children were among the casualties, Ahmadi said.
ISAF said more than 10 Afghan civilians were killed and several others, "in an explosion triggered by insurgents in a crowded area."
Stiff condemnations were also issued by the United States, the United Nations, and ISAF.
"The planting of improvised explosive devices on roadways either targeting civilian transport or indiscriminately affecting civilians is against international humanitarian law. There can be no justification for such action," said Staffan de Mistura, the U.N. secretary-general's special representative for Afghanistan.