DAHANEH, Afghanistan » The British jet called in by Kaneohe Marines had the Taliban position in sight, but the pilot refused to fire, a decision that frustrated Marines on the ground but was in line with new orders by the top U.S. commander to protect civilians.

During the same battle Wednesday, the Marines themselves did not attack militants shooting at them from a compound because women and children were there, an approach meant to avoid civilian casualties at all costs.

“;They did that on purpose,”; sniper platoon leader 1st Lt. Joseph Cull, 28, of Delafield, Wis., said of the Taliban. “;They are trying to bait us.”;

Gen. Stanley McChrystal, the top U.S. and NATO commander in Afghanistan, has made protecting Afghan civilians his top priority. The approach is a shift away from a military mindset with a traditional first response to kill as many militants as possible. By holding fire, McChrystal hopes to avoid the massive civilian casualty cases of past months and years and help win over Afghan villagers.

U.S. Marines have been locked in battle with insurgents in Dahaneh in Helmand province after they stormed into the Taliban-held town earlier this week. Militants have been lobbing rocket-propelled grenades, mortars and heavy machine gun fire at the U.S. troops.

The troops hope to break the Taliban's grip in Dahaneh, sever smuggling routes and protect civilians from Taliban reprisals so Afghans can vote here during Thursday's presidential election, which the Taliban have vowed to disrupt.

The Marines locked in on a Taliban position Wednesday in a cave in a nearby mountain, from which militants were firing heavy weapons. The troops called for an airstrike against the position, but the British Harrier jet that responded refused to fire its missiles because British rules of engagement require the pilot himself to identify the target, not just troops on the ground.

Each country in the more than 40-nation NATO-led coalition in Afghanistan has its own rules of engagement that apply to specific battle situations, but McChrystal's order to protect civilians applies to all forces in the country.

“;Sure, that's frustrating, but we've got to deal with it,”; said Capt. Zachary Martin, commander of Golf Company, 2nd Battalion, 3rd Marine Regiment, based at Kaneohe Bay.

Some 400 Marines and 100 Afghan troops moved into Dahaneh by helicopter and ground convoy. The troops took heavy fire from insurgents for most of the day, killing up to 10 militants after calling in an airstrike on an insurgent position.

But even that airstrike was carried out with great care.

Militants first started firing from the position at about 5 a.m. Ground commanders wanted an airstrike called in on the position to help protect Marines receiving fire. But superior officers wanted to be certain there were no civilians there.

Once Martin had established with near certainty that there were not, an airstrike hit the compound—hours after the Marines first received fire.

The Marines say they can avoid civilian casualties with the help of the sophisticated surveillance technology they have. Strict orders have also been issued for the Marines to use proportional response when attacked.

But many of the riflemen voiced frustration at the limited options they were left with when trying to expand control of the town on Wednesday. The orders to hold fire appeared to have slowed their advance in Dahaneh, where after a full day they held only a small foothold outpost.

Yesterday the Marines expected another day of intense combat as they pushed deeper into the town. Insurgents seemed unwilling to fight overnight, when they cannot match the Marines' night-vision capabilities. But after the sun came up yesterday, the first rounds of fire erupted.

“;Right on cue!”; shouted Sgt. Ryan Kelsey of Pittsburgh as the first shots rang out.