KANDAHAR, Afghanistan (Reuters) – A suicide attack aimed at NATO-led forces killed two Danish soldiers and at least three Afghan civilians on Monday in the southern province of Helmand, officials said.

The Danish Army Central Command said another of its soldiers was wounded in the attack, in Girishk district of the province. The soldiers were working on a reconstruction project when they were attacked, it said.

A spokesman for British forces in Helmand said the NATO-led International Security Assistance Force (ISAF) had suffered casualties — either dead or wounded — but denied media reports that four British soldiers were killed.

“That is completely untrue. As yet, all I can say is that there were ISAF casualties,” Lieutenant Colonel Simon Miller said.

“We are still waiting for confirmation of nationalities and types of casualties and I am not aware of four British soldiers being killed, that is wrong,” he said.

The attacker was in a car, but failed to hit the NATO convoy traveling in the Girishk district of Helmand, one of the areas where Taliban guerrillas are most active and the region that alone produces nearly half the world’s opium, the Helmand police chief said.

“Three civilians were martyred and seven more were wounded in the attack,” police chief Mohammad Hussein Andiwal told Reuters.

British soldiers form the bulk of the International Security Assistance Force in Helmand.

Violence in Afghanistan has spiraled since the hardline Islamist Taliban relaunched their insurgency to topple the pro-Western Afghan government and eject foreign troops two years ago.

The Taliban rely heavily on suicide and roadside bomb attacks, but as foreign forces use more heavily armed vehicles and are becoming better at avoiding casualties, a greater proportion of the victims are Afghan civilians.

The Taliban carried out more than 140 suicide attacks last year. The militants, who the U.S.-led troops overthrew from power in 2001 for harboring al Qaeda leaders, have vowed to step up the suicide bombing campaign this year.

More than 12,000 people, including some 350 foreign soldiers, have been killed since 2006 in Afghanistan, according to United Nations estimates.

On Sunday night, a Canadian soldier was killed by an explosion in Kandahar, ISAF said.