KABUL, Afghanistan - Taliban fighters and their commanders have escaped the Marines' big offensive in Afghanistan's southern Helmand province and moved into areas to the west and north, prompting fears that the U.S. effort has just moved the Taliban problem elsewhere, Afghan defense officials said.

The movement of the Taliban into those areas has prompted complaints from German and Italian commanders, whose troops operate there, and it has prompted questions about whether the United States has enough troops to pursue the Taliban while at the same time carrying out Army Gen. Stanley McChrystal's plan to "clear, hold, and build" in areas wrested from Taliban control.

Last week, the national security adviser, James L. Jones, said no additional troops would be sent to Afghanistan this year, even as some NATO nations threaten to draw down their presence.

Even with the addition of 17,500 troops ordered by President Obama to Afghanistan, commanders fear they will not have enough troops to clear large swaths of the country and then hold them.

Since the Marines began their offensive Thursday, Taliban fighters have moved to northern parts of Helmand province, near Baghran, an area controlled by German forces, and the eastern edge of Farah province, largely under Italy's control, said Gen. Zahir Azami, the Afghan Ministry of Defense spokesman.

In at least one case, Taliban fighters donned women's tentlike burqas and held children's hands to pass disguised as women to flee from a compound in the Helmand River Valley, said Brig. Gen. Mahaiddin Ghori, the Afghan commander in Helmand.

U.S. and Afghan military officers said that in many cases, fighters left behind roadside explosives as they fled. A Marine and an Afghan soldier have been killed in the operation, both by explosives.

The offensive, Operation Khanjar, or "Strike of the Sword," involves 4,000 Marines and 750 Afghan troops.

Besides clearing one of Afghanistan's most dangerous provinces, the operation is intended to signal to local residents the United States intends to stay behind to begin building local governance.

U.S. and NATO officials acknowledged the Taliban fled Helmand ahead of the Marines. But the officials said they feel the fighters are still contemplating how to respond to the operation.

Along the Afghan-Pakistan border yesterday, suspected U.S. missiles and Pakistani fighter jets attacked followers of Pakistani Taliban leader Baitullah Mehsud.

Two missiles hit a training camp run by Mehsud in the South Waziristan tribal region, killing 12 to 14 insurgents, but not Mehsud, intelligence officials said on condition of anonymity because they were not authorized to speak to media.

Hours later, Pakistani war planes bombed extremist positions 25 miles away, the army said. Casualties in those strikes were unknown.