As fighting between Taliban insurgents and Afghan and NATO soldiers entered its third day yesterday in Helmand province, coalition leaders were left handling a series of civilian deaths that threaten to derail popular support for the offensive.

In two days, coalition troops have killed as many as 20 civilians in five separate incidents in two Afghanistan provinces.

Three men were shot and killed after being individually mistaken for insurgents; five men were killed in an air strike yesterday after Canadian-commanded troops erroneously thought they were planting bombs; and as many as 12 civilians were killed in a high-profile rocket attack a day earlier, the details of which remained unclear amid varying accounts yesterday.

The civilian deaths come as some soldiers complain that Taliban insurgents are avoiding coalition gunfire by ducking in and out of civilian areas, possibly drawing the fight to the local population.

The deaths are a particularly heavy blow to Operation Moshtarak, the continuing push into the Taliban strongholds of Marjah and Nad Ali in Helmand.

Named for the Dari word meaning ``together,'' Operation Moshtarak was designed as wholly civilian-friendly in an effort to build trust in the Afghan government. The mission included leaflets warning the local population an attack was coming, and was meant to avoid precisely the types of deaths International Security Assistance Force has since been forced to announce.

``This operation ... is not about battling the Taliban. It is about protecting the local population and you don't protect them when you kill them,'' said Air Chief Marshal Jock Stirrup, chief of Britain's defence staff. He called the rocket attack a ``very serious setback'' in the effort to win the support of the Afghan people.

In a statement announcing the deaths of the three shooting victims, Colonel Steven Baker of ISAF Joint Command said such incidents ``represent some of the most difficult situations being faced by Afghan and ISAF forces conducting Operation Moshtarak. Our forces are continuing to do everything they can to protect civilians.''

Meanwhile, coalition leaders have offered conflicting accounts of Sunday's deadly rocket attack.

On Sunday, Afghan President Hamid Karzai had said 10 civilians were killed in the attack in Nad Ali. Later that day, ISAF said 12 civilians were killed when two rockets hit the wrong target.

But yesterday, Afghan Interior Minister Mohammad Hanif Atmar said only nine civilians were killed, along with two or three insurgents who he suggested had sought refuge in the home during a battle with coalition troops. He said the rockets were meant for the house.

``The reality is this - the enemy did capture some civilians in their house and they were firing at our forces from this house. Unfortunately our forces didn't know that civilians were living in that house and as a result of this incident nine civilians were killed and ... two or three fighters were killed,'' the minister told the press conference.

However, reporters accompanying U.S. Marines involved in fighting nearby said the Americans were surprised by the rocket attack, immediately investigated and found 11 dead - five children, four women, and two men, according to a New York Times report. Another report said six children died.

After first saying the rockets landed 300 metres off-target, ISAF said yesterday the target was 600 metres away. Others supported the Interior Minister's claim, saying the rockets had been aimed at the house.

``The rocket hit the house that we wanted it to hit,'' a U.S. officer told the Times. ``We didn't know there were civilians there.''

Details on the other civilian deaths were slim.

One man died Sunday after he and another were caught in a gun battle in a building being used by insurgents. ISAF medics treated the men, but couldn't save one. In separate incidents Sunday and yesterday, two men died after being shot after ignoring hand signals to stop approaching coalition soldiers.

Earlier in the day, an air strike in the Zhari district of Kandahar province - unrelated to Moshtarak - killed five civilians and wounded two others. The air strike was ordered by a joint Afghan-NATO patrol that thought the civilians were planting makeshift bombs.

Operations in Zhari are led by a Canadian general and include Canadian and other troops. Both ISAF and Canadian Forces spokesmen declined last night to say if Canadians were involved.

Operation Moshtarak continued yesterday with fighting concentrated in Marjah. An Afghan military commander said the Taliban had been nearly eradicated from Marjah, but reporters embedded with U.S. troops reported persistent insurgent sniper fire.

Soldiers have been slowed by a maze of makeshift bombs placed throughout Marjah. When the soldiers do see insurgents, the men often drop their weapons and begin to blend in among the local population before coalition troops can open fire.

``They're using our rules of engagement against us,'' said Marine Lance- Corporal Travis Anderson. ``I understand the reason behind it, but it's so hard to fight a war like this.''