KHOST, Afghanistan — Afghan President Hamid Karzai on Thursday ordered an investigation into provincial government claims that a NATO raid killed six civilians in the restive east.

Government officials said the six, including an 11-year-old girl, died during a military operation targeting the Al-Qaeda-linked Haqqani network.

NATO said its troops killed insurgents linked to the Haqqani network during gunfights in the area and that only one civilian was wounded.

But a demonstration broke out after bodies of the dead were carried through the eastern city of Khost and the provincial council announced it was going on strike in protest over the deaths.

Karzai ordered provincial officials to conduct a "broad based investigation into civilian casualties in coalition operations in Khost province", said a statement from his office.

"The president instructed the Khost governor Abdul Jabar Naeemi and other security officials to closely investigate the circumstances around the incident and submit their report to the president at the earliest possible," it said.

Civilian casualties are an inflammatory issue between US-led foreign forces and Karzai who issued a "last warning" to the military in early June to avoid "arbitrary and unnecessary" operations that kill civilians.

"A teacher, a student, an 11-year-old girl and three other ordinary people were killed in the operation. They were civilians, innocent people," said Khost provincial spokesman Mubarez Zadar.

"The coalition forces were given the wrong information and based on wrong information, they carried out an operation," he said.

The provincial council said it had gone on strike in protest.

A statement from NATO's International Security Assistance Force (ISAF) said it had reports of only one female civilian wounded during a battle with insurgents and that she had since been given medical treatment.

ISAF said six Haqqani fighters had been killed, including one armed woman.

"The security force was attacked by several armed insurgents while attempting to clear a compound near a coalition base in the district," it said.

The military said the fighters were killed in three subsequent firefights, all of which were triggered by insurgent gunfire.

On Thursday, the United Nations said the number of civilians killed in the Afghan war in the first half of 2011 was up 15 percent, putting the year on track to be the deadliest in a decade.

The UN mission in Afghanistan said insurgents accounted for 80 percent of civilian deaths in the past six months and NATO troops 14 percent of killings.