Coalition troops continued to fend off tough areas of resistance as they pushed ahead. A British plane was shot down by a U.S. missile during one mission.
Taking aim: U.S. soldiers try to secure a farming area near the southern Iraqi city of Basra on Saturday.
U.S. Marines pressing into Iraq have learned one lesson already -- this is not a training exercise. It is a life-and-death fight, and some of them don't like what they have seen.
The fighting "was totally different than any experience in my life," said Lance Cpl. Daymond Geer, 20, of Sacramento, California. "Even seeing the enemy get shot. Well, he was squirming in the dirt. It was not good."
Geer and other members of the 15th Marine Expeditionary Unit received their bloody baptism on Friday as they cleared an area of bunkers in southern Iraq, near the port of Umm Qasr. Scores of Iraqi soldiers surrendered, many walking toward the Americans in strict military formation under a white flag.
There were bursts of gunfire, often rapid machine-gun fire, and the heavy thud of hand grenades. By the end of the day, Geer's company had lost one Marine, killed five Iraqis and taken 400 prisoners.
Cpl. Juan B. Elenes, 21, of Portland, Oregon, killed one of the Iraqis. He said afterward that he had had enough. "OK. I'm done. I'm ready to go back to Kuwait now," Elenes said.
But that was not an option for him and the thousands of other U.S.-led troops pressing deeper into Iraq in the drive to overthrow Saddam Hussein. By Sunday, the U.S.-led forces had crossed the Euphrates River and were nearly half way to Baghdad. But they have been facing stiffer than expected Iraqi resistance the farther north they go.
The drive was accompanied by two incidents in which members of the U.S.-led force inflicted casualties on their comrades. A U.S. soldier was arrested after grenades were thrown into a 101st Airborne command center in Kuwait early Sunday, killing one and wounding 13 servicemen, the U.S. Army said. And a U.S. Patriot missile downed a Royal Air Force plane late Saturday or early Sunday, an American military official said.
The following is a summary of the fighting:
The Euphrates River Area
U.S. and British troops heading for Baghdad have gained control of Nasiriyah, a key passage point across the Euphrates River that is about a third of the way up to the capital, U.S. military spokesmen said. But anxious to avoid nasty, house-to-house fighting, they chose not to enter Nasiriyah on Saturday.
In the nearby town of Tellil, the outnumbered Iraqis fought on. U.S. Army Lt. Col. Jim Lackey said the Iraqis had more spunk than organization. "It was sporadic," Lackey said. "There was no one directing them. They were just throwing things out there."
Iraqi state television reported fighting between Iraqi ruling Baath party militias and U.S.-British forces near the Shiite holy city of Najaf, 95 miles (150 km) south of Baghdad.
U.S. Army infantry battled Iraqi troops throughout the day at the city of As-Samawah, downriver from Najaf and 150 miles (240 km) south of Baghdad, as the Americans seized two bridges across a canal near the Euphrates' southern bank.
U.S. Marines near the port city of Umm Qasr.
Farther south, U.S. Marines battled Saturday with Iraqi commandos, some wearing civilian clothes, around Umm Qasr, Iraq's sole deep-water port on the Persian Gulf. Heavy bursts of gunfire and loud explosions from tank shells resonated across the dusty battlefield on the outskirts of the town as Marines blasted Iraqi positions.
"The city is under control," but commandos are still hiding around the city, Marine Lt. Col. Steve Holmes said. "It's probably not going as quick as we would have liked."
Lt. Col. Chris Vernon, a British military spokesman, said some of the fighters had changed into civilian clothing to blend in with the population. "It's easy to sit in a window and fire a rifle," Vernon said.
Coalition troops say they want to secure the town so that the port can be used for humanitarian shipments.
The Iraqi capital remains the target of a forbidding aerial assault. Several more fierce blasts rocked the capital where the United States has been pounding away at key symbols ofSaddam Hussein's 24-year iron grip on power. Orange fireballs lit the sky late Saturday around Baghdad airport.
Electricity in parts of south Baghdad was briefly cut after several explosions were heard Saturday night. More blasts shook the city early Sunday.
A U.S. military spokesman at As-Saliyhah, Qatar, said on Sunday that he could not provide additional details about the downing of the Royal Air Force plane.
A Ministry of Defense official in London said it was not yet possible to say what sort of plane was involved or how many crew members it had because no families had been contacted. He also declined to describe the plane's mission.
A spokesman for British forces in the Gulf said a joint investigation has been set with the U.S. military to determine what happened. "Obviously, everyone is eager for explanations. We need to know," Group Capt. Al Lockwood told the BBC. "This is a tragedy, and we are taking rapid steps to find out the reasons and to ensure that there is no repetition."
The issue of friendly fire is one that can haunt military commanders. During the first Persian Gulf War, 35 of the 148 U.S. combat deaths resulted from what the military now calls "fratricide." A further 78 U.S. soldiers were wounded by their comrades, making the phenomenon responsible for 17 percent of all American casualties.
Since then, the issue has not gone away. Last year, a U.S. fighter pilot dropped a laser-guided bomb on Canadian forces in Afghanistan, killing four soldiers and wounding eight.
An attack occurred about 1:30 a.m. Sunday in the command center of the 101st Division's 1st Brigade at Camp Pennsylvania in Kuwait. The attacker threw three grenades into three tents, including the command tent, military officials said. The motive in the attack "most likely was resentment," said Max Blumenfeld, a U.S. Army spokesman. He did not elaborate.
The name of the soldier who died was not released because family members had not been notified, said George Heath, civilian spokesman for Fort Campbell, Kentucky, the division's home base.
"Incidents of this nature are abnormalities throughout the Army, specifically in the 101st," Heath said.
The suspect was found hiding in a bunker. He is an engineer from an engineering platoon in the 101st Airborne, said Col. Frederick B. Hodges, commander of the division's 1st Brigade.