BAGHDAD, Iraq - Five U.S. Marines died in an ambush on the Syrian border, triggering a battle with hundreds of guerrillas and pushing the number Americans killed in combat this month to 99.
Reports of the battle - in an area that had seen little fighting previously - came as Spain's prime minister ordered Spanish troops withdrawn from Iraq as soon as possible. Prime Minister Jose Luis Rodriguez Zapatero had run for office on a promise to withdraw the forces, but the timing of the announcement was unexpected.
At least 25 Iraqis were killed in the fighting that followed Saturday's ambush in Husaybah, 240 miles west of Baghdad, the military said. The city's police chief was among the dead, a hospital official said.
Across Iraq, Saturday was one of the bloodiest days for U.S. troops since the latest uprising began April 4. Five U.S. troops were killed in guerrilla attacks elsewhere in the country and a sixth died in a tank rollover.
Meanwhile, U.S. forces struggled to maintain control of Iraq's highways. The military announced new closures around Baghdad that severed long stretches of roads into the capital from the north, south and west - a reflection of the damage from a two-week guerrilla onslaught on U.S. supply lines.
Insurgent attacks and kidnappers' roadblocks have forced the military to curtail supply convoys and are part of the reason commanders have boosted ground forces by more than 20,000 U.S. troops. The military has already been tied down since April 1 on fronts in southern and central Iraq in the worst violence since the fall of Saddam Hussein.
Officials have said the violence threatens to hamstring U.S. reconstruction effort and drive up prices of civilian goods, dealing a blow to a delicate economic recovery in Iraq.
More than 1,500 foreign engineers and contractors have fled Iraq for fear of being abducted or killed, Iraqi Housing Minister Bayan Baqer said Sunday.
The military in Baghdad on Sunday announced the death of five U.S. troops the day before in attacks across Iraq.
Three soldiers were killed when their 1st Armored Division convoy was ambushed near the southern Iraqi city of Diwaniyah. Another died when a roadside bomb exploded near a military convoy in Baghdad, and a Marine was killed in action in western Iraq, separate from the fighting by the Syrian border.
Along with the fighting at the border, the deaths brought to 99 the number of U.S. troops in violence killed since April 1. With the death of a soldier in a tank rollover in Baghdad on Saturday, at least 697 U.S. servicemembers have died in Iraq since the war began in March 2003.
Defense Secretary Donald Rumsfeld said last week he had not anticipated such a high death toll. Gen. Richard B. Myers, the chairman of the Joint Chiefs of Staff, said Sunday there was no way to predict casualties.
"This is combat, this is war. This is much more art than it is science. There is no way to make a proper calculation," he said in an interview with CNN.
Rockets aimed at a military camp in western Baghdad hit a nearby civilian area, killing two Iraqi civilians and wounding four others, as well as wounding two U.S. civilian contractors and one soldier.
The fighting in Husaybah began when insurgents ambushed Marines on Saturday, sparking a battle with hundreds of rebel gunmen.
Fighting continued Sunday in three neighborhoods of the city, which was sealed off by U.S. forces.
Five Marines were killed in the fighting, said Marine spokesman Lt. Eric Knapp. He also said some Marines were wounded, but did not give a number. He reported 25-30 insurgents were killed.
At least 30 Iraqis were wounded, Hamid al-Alousi, a doctor at the hospital in the nearby city of al-Qaim, told the Arab television station Al-Arabiyah. He said some civilians were shot by Marine snipers as they stepped outside to use outdoor toilets behind their houses.
Husaybah police director Imad al-Mahlawi was one of those killed by American snipers, according to a man who identified himself as al-Mahlawi's cousin, Adel Ezzeddin, Al-Arabiya reported.
According to Marine intelligence, nearly 300 Iraqi mujahedeen fighters from the Fallujah and Ramadi areas, some 150 miles to the east, launched the offensive in an outpost near Husaybah.
They first set off a roadside bomb to lure Marines out of their base, and then fired 24 mortars as the Marines responded to the first attack, said a correspondent from the St. Louis Post-Dispatch who is embedded with the military.
Myers said U.S. forces are on the border to try to stop foreign fighters from entering Iraq. He complained that Syria was not doing enough to control the border.
"The Syrians need to take this situation very seriously," he said. "I want them to cut off that flow of foreign fighters."
The announcement that Spain would pull out its 1,300 soldiers came just hours after a new Socialist government was sworn in.
In an announcement from the Moncloa Palace, Zapatero said he had ordered the defense minister to "do what is necessary for the Spanish troops stationed in Iraq return home in the shortest time possible."
The Socialists swept to an election victory after March 11 train bombings killed 191 people in Madrid. Militants who claimed responsibility for the attack said it was punishment for backing the United States in the war.
Zapatero said he acted after deciding the United Nations was unprepared to take over the occupation of Iraq - his condition for keeping Spanish troops in the country.
The military announced Sunday it closed off the main highway from Baghdad to the Jordanian border, the scene of heavy fighting at the western entrance to Baghdad as well as near Fallujah and Ramadi further down the road.
For days, gunmen along the route have been attacking convoys and kidnapping foreigners - including an American soldier and civilian.
The military also shut down a stretch of the main highway north to Turkey, starting at the entrance to Baghdad extending to the town of Balad 42 miles north. Also closed was a 90-mile section of the main southern highway connecting Baghdad with Basra and Kuwait.
In other developments Sunday:
- U.S. National Security Adviser Condoleezza Rice said she would not speculate on whether the United States might consider a prisoner swap with militants who have kidnapped Americans, but added, "I think you can be certain that negotiations with terrorists are not on this president's agenda." She spoke on "Fox News Sunday."
- Two British soldiers were injured Saturday when their convoy came under fire in the southern town of Amarah, but their injuries were not life-threatening, the British defense ministry said Sunday.
- Attackers fired several mortar rounds overnight at Spanish bases in Diwaniya and Najaf, and at a Polish base in Karbala, but no damage or casualties were reported.