KABUL, Afghanistan – Taliban fighters carrying machine guns and rocket-propelled grenades used children as human shields during a battle in southern Afghanistan on Wednesday, forcing U.S.-led coalition soldiers to hold their fire for a time, the coalition said.

The clash in Uruzgan province began when more than 20 insurgents attacked a joint Afghan and coalition patrol, the coalition said in a statement.

As aircraft prepared to bomb the site, “coalition forces as well as the aircraft identified several insurgents in one compound using children as human shields,” the statement said. Ground troops and the aircraft withheld fire to avoid injuring the children, it said.

The soldiers did fight the insurgents when they tried to flee the compound, and more than a dozen suspected militants were killed, the coalition said. The report, which was impossible to verify independently, did not list any casualties among troops or civilians.

Maj. Chris Belcher, a coalition spokesman, said Taliban militants have used children as shields before. In June, insurgents forced women and children into a canal in Uruzgan while battling coalition forces, and many of the human shields died in the crossfire, he said.

“If you look at some of the actions where the Taliban have had women and children carrying ammunition for them, where they’ve used civilian houses, and now in this case they’re using children to shield themselves, I’d say that shows they really don’t care about Afghans,” Belcher said.

The U.S.-led coalition and the NATO force in Afghanistan themselves were strongly criticized earlier in the year by President Hamid Karzai and others for causing civilian casualties in airstrikes on suspected militant locations. The number of such casualties has dropped recently.

Also Wednesday, NATO said it was investigating a weapons shipment recently intercepted by troops in Farah province near the Afghan border with Iran.

“Although we know that it came from the geographic area of Iran, there is no definitive indication that it came from the Iranian government. We’re still evaluating what is contained in that shipment,” a NATO spokesman, Maj. Charles Anthony, said.

A Washington Post report Sunday said the shipment seized Sept. 6 was being sent to the Taliban and included armor-piercing bombs similar to those that have been used against foreign troops in Iraq.

Troops intercepted two other shipments said to be from Iran earlier in the year, but NATO’s top general in Afghanistan, Gen. Dan McNeill, has said there is no evidence linking them to the Iranian government.

Last month, President Bush accused Iran of playing a destabilizing role in Afghanistan. But Karzai has called Iran’s role helpful.

During a visit to Kabul last month, Iranian President Mahmoud Ahmadinejad said he had “serious doubts” that his country was supplying weapons to Taliban insurgents. He called Afghanistan a “brotherly nation” whose stability is paramount for the region.

About 2,500 Afghan and NATO soldiers launched an operation Wednesday in the Gereshk region of Helmand province. The southern province has been the site of the fiercest battles this year and is the world’s largest opium-producing region.

The NATO command said the troops would conduct “security and stabilization” operations in the upper Gereshk Valley, but provided no other details.

Insurgency-related violence has killed more than 4,500 people this year, including 3,100 militants and 600 civilians, according to an Associated Press tally of figures from Western and Afghan officials.

The U.S. Embassy in Kabul warned American citizens that suicide bomb attacks were expected to increase during the holy month of Ramadan. One such attack wounded eight Afghan policemen in Helmand’s Garmsir district, while another suicide bomber blew himself up on the road leading to the U.S. air base at Bagram without causing other casualties.

In southern Zabul province, Taliban militants killed three security guards protecting a construction project in Qalat, said Gulab Shah Alikhail, spokesman for the governor.

Associated Press writer Noor Khan in Kandahar contributed to this report