Iran's supreme religious leader, Ayatollah Ali Khamenei, weighed in on the side of anti-American Shiite Muslim insurgents in Iraq, chastising U.S. actions across the southern part of the country as "stupid" and "shameful."

Khamenei's remarks, made in a speech to theology students and broadcast on Iranian radio, were the first harsh criticism issued by predominantly Shiite Iran about the ongoing U.S. offensive against forces loyal to Moqtada Sadr, a young Shiite cleric wanted by U.S. forces on murder charges.

Shortly after Khamenei spoke, about 100 students threw rocks at the British Embassy in Tehran and burned the British and Israeli flags.

Meanwhile, U.S. officials reported that a U.S. soldier died late Sunday of wounds suffered during a firefight in an unspecified city in southern Iraq.

In Basra, the largest Shiite city in Iraq, insurgents firing at a British camp hit a house instead, British officials said. The blast killed four Iraqi civilians, including 2-year-old twins, news services reported.

A female translator working with U.S. troops was killed and another was critically injured when gunmen broke into their houses in Mahmudiyah, about 20 miles south of Baghdad, said Dawood Taee, director of the city's hospital.

And in Baghdad, gunmen fired at a minibus carrying five female employees of the U.S.-led occupation authority. Two women were killed, and a third lost an eye. As the survivors fled, the insurgents blew up the bus. Its twisted remains stood abandoned in front of the Daura neighborhood police station all day Sunday. "What can we do about this?" said Capt. Ali Omran, who was in charge of the station. "We get shot at ourselves."

In the year since the fall of Iraqi President Saddam Hussein, Iran's position toward the U.S.-led invasion and occupation has had two sides. The Supreme Council for the Islamic Revolution in Iraq, an Iraqi group that is largely cooperative with the United States, has the support of Iranian President Mohammad Khatami. The Supreme Council and Grand Ayatollah Ali Sistani, Iraq's most senior religious authority, have urged U.S. forces as well as Sadr and his militia to withdraw from Najaf.

But Sadr, who has recruited loyalists from among the legion of poor Shiite youths in Iraq, is financed by an ayatollah in the religious city of Qom in Iran. The ayatollah, Kazem Haeri, is backed by officials of the Revolutionary Guards and Iranian intelligence agencies, U.S. and Iraqi officials say.

Khamenei, in his speech Sunday, said, "The Americans' military aggression against holy Shiite sites is a rude, shameful and stupid measure," according to excerpts reported by the official Islamic Republic News Agency.

He accused U.S. troops of firing on and hitting the golden dome of the Ali shrine, which is dedicated to the first Shiite imam. "Muslim people, particularly Shiites, in their own country or in Iraq, in various Iraqi cities or in other parts of the world, will not remain silent at this American encroachment," he said.

Khamenei also criticized the operation of Abu Ghraib prison, where U.S. guards abused Iraqi prisoners. "You have not closed Saddam's torture chambers. You have replaced Saddam," he said.

"The Americans are trapped," he said. "There is nothing they can do. They will fail if they continue on this path, and they will fail if they pull out."

Najaf, where Sadr has taken refuge among hundreds of militiamen, was relatively quiet Sunday, residents said. The day before, U.S. troops pursued Sadr loyalists and used tanks to fire on those who had taken up positions in a huge cemetery in the city. Shiites consider the cemetery the world's most desirable burial place because of its position close to the Ali shrine.

A few dozen demonstrators marched in Najaf on Sunday, demanding the withdrawal of forces on both sides, witnesses said.

In Nasiriyah, south of Najaf, insurgents attacked a convoy transporting Italy's civilian administrator for southern Iraq, Barbara Contini, as it approached the occupation administrative offices. The official was uninjured, but two Italian paramilitary police officers suffered injuries, according to news reports from Rome.

Insurgents also drove Italian troops from their base in Nasiriyah, the Associated Press reported. The Italians evacuated the base Sunday as it came under repeated attack. At least 10 Italians were wounded, one of them critically, according to Lt. Col. Giuseppe Perrone, a spokesman for the Italian force.

Gunmen and rebels bearing rocket-propelled grenade launchers earlier attacked the occupation building in Nasiriyah, where the Italians are deployed. It was the third consecutive day of skirmishes there.

Italian Foreign Minister Franco Frattini, in a rare criticism of the United States, wrote in the Corriere della Sera newspaper: "We have asked the Americans to avoid frontal attacks on Iraqi holy cities and to hand over military control of these cities to Iraqi forces." He did not specify which forces.

The government of Italian Prime Minister Silvio Berlusconi is under pressure from opposition groups to withdraw Italy's 2,500 troops from Iraq. Frattini suggested, however, that Italy has no plans to pull out. "There is one point on which everyone agrees," he wrote. "If there was an immediate pullout by the coalition, Iraq would fall into civil war."

But Gianfranco Fini, who heads the second-largest party in Berlusconi's coalition, said the government was looking for a way out. "An exit strategy is being defined," he told reporters, referring to Italian efforts to get the United Nations involved in pacifying Iraq. Spain withdrew its forces from Iraq last month.

Also Sunday, the Arab satellite television network al-Jazeera broadcast footage of two Russian hostages held in Iraq since Monday and read a statement from a group demanding that foreign troops withdraw from the country, the Associated Press reported.

The brief footage showed the two men, seemingly in good health, sitting against a wall.