Deadly ambush teams struck U.S. Army targets from west to north in the arc of resistance around Baghdad (search), and the interim Iraqi leader called Sunday for an immediate mobilization of the old Iraqi army to help the harried Americans.

The United States would "speed the process of relieving the burden on its troops" by recalling the disbanded Iraqi military, said Iyad Allawi, current president of the Iraqi Governing Council (search). The idea got a cool reception, however, from Baghdad's U.S.-led occupation authorities.

Attackers killed two U.S. soldiers in a clash outside the northern city of Kirkuk (search) late Saturday, and others blasted a broken-down convoy in the western flashpoint city of Fallujah (search), setting off spectacular explosions from an ammunition truck.

One Iraqi civilian was killed by the blast and at least four were wounded in Fallujah, either from the blasts or from gunfire from American troops as they sped away, hospital officials said.

In the attack near Kirkuk, 160 miles north of Baghdad, an American mounted patrol was ambushed by rocket-propelled grenades and small arms fire at 10:45 p.m. Saturday, said Maj. Josslyn Aberle, 4th Infantry Division spokeswoman. The patrol returned fire, but no additional enemy contact followed, she said.

In addition to the two killed, a third American was wounded, Aberle reported.

Early Sunday, about 30 miles west of that attack, U.S. troops were hit with grenades and small arms fire near Hawija, and killed three Iraqis when they returned fire, the 4th Infantry Division reported. Still farther west, near Beiji, American forces detained five attackers after a brief firefight, the division said.

On the eastern edge of Fallujah, 35 miles west of Baghdad, a U.S. Army ammunition truck, part of a convoy, broke down on the main road late Sunday morning and came under attack, the U.S. command said in Baghdad. The truck and possibly two other vehicles apparently were hit by rocket-propelled grenades.

"Shells were flying everywhere, like fireworks," shopkeeper Khalil al-Qubaisi, 45, said of the exploding ammunition truck. Dozens of Iraqi youths danced and cheered as the vehicles went up in flames.

U.S. troops trying to approach the site pulled back after coming under grenade attack, and opened fire in every direction as they left, witnesses said.

"I was fixing my car on the other side of the street, and Americans fired in a circular motion as they tried to leave," said Thaer Ibrahim, 30, who was wounded in the shoulder by the American fire.

Four other civilians were wounded, and one later died of shrapnel wounds, said Dr. Rafae al-Issawi, director of Fallujah General Hospital. In Baghdad, the U.S. command said there were no American casualties.

In nearby Khaldiyah, unidentified assailants fired two rocket-propelled grenades at two Humvees, damaging one, said a witness, shopkeeper Adel Kamel. It was unclear whether there were any casualties.

The deaths in Kirkuk brought to 103 the number of Americans killed by hostile fire since President Bush declared an end to major combat on May 1. A total 338 Americans have died since the invasion of Iraq in March, 217 of them in combat.

The command reported 15 attacks on forces of the U.S.-led coalition in the 24 hours ended at midday Sunday, down from a recent average of 22 a day. Most occur in the so-called "Sunni Triangle," a Sunni Muslim-dominated area stretching from the west of Baghdad to the north. The area was a strong base of support for Saddam Hussein's Baath Party regime, toppled by the U.S.-British invasion earlier this year.

American officials blame the insurgency largely on die-hard Baathists, but many here believe other Iraqis resentful of the U.S. military presence have joined in the hit-run attacks.

In an opinion-page piece in Sunday's New York Times newspaper, Allawi, head of the 25-member Governing Council for the month of October, said the decision by U.S. occupation officials to dissolve the 400,000-man Iraqi army after the war's end in April produced a "security vacuum that let criminals, die-hards of the former regime and international terrorists flourish."

Allawi wrote that it is "vital" to recall Iraqi army units now, six months after they disintegrated before the U.S.-British military advance. The U.S. government has had little success enlisting significant foreign military help in Iraq, but a well-placed official of the occupation authority reacted coolly Sunday to Allawi's position.

"I don't think there's a vast swath of people out there who want to serve in the Iraqi army," said this official, speaking on condition of anonymity.

The Americans are slowly rebuilding a new Iraqi army, having trained only a 700-man battalion thus far.

Allawi's council, meanwhile, issued a statement Sunday urging Iraqis "to remain calm and prevent incitement engulfing the country."

The Bush administration is urging other nations to send troops and money to help the United States in Iraq. Washington hopes that last week's unanimous U.N. Security Council vote on a U.S.-sponsored resolution on Iraq will prompt nations to contribute.

"We'll take as much money as we can get," Secretary of State Colin Powell said ahead of a donors conference due to begin Thursday in Madrid.

"And I think the resolution will encourage some countries to give who might not have had a basis to give before the resolution was passed," he said on "Fox News Sunday."