U.S. and British troops swept into southern Iraq on Thursday in an invasion aimed at Baghdad, where a new wave of missiles and bombs struck a presidential compound housing several government departments at the heart of Saddam Hussein's power.
The ground fighting marked an escalation in a war meant to drive Hussein out. Many had expected it to begin with a massive bombing campaign, but officials in Washington said this was only the prelude, intended to dismantle the Iraqi leadership and avoid a full-scale war.
A Pentagon official said the United States had stepped up its psychological warfare campaign aimed at persuading Iraqi forces to surrender.
One U.S. official reported some signs of disarray in the Iraqi army, and Defense Secretary Donald H. Rumsfeld said, "We still hope that it is possible that [Hussein's regime will collapse] without the full force and fury of a war."
But if full-scale military operations become necessary, Rumsfeld said, they will be of "a scope and a scale that is beyond what has been seen before." Defense officials have said the United States would rain down 3,000 bombs on the first of 7,000 designated targets during only the initial two days of such a massive campaign.
In the first allied deaths of the war, a U.S. Marine CH-46 Sea Knight helicopter crashed in Kuwait early today, killing 12 American and British troops on board, a U.S. defense official said. The Americans were from the 1st Marine Expeditionary Force, based at Camp Pendleton. A British official said eight of the dead were British and four were American.
The helicopter crashed as the troops tried to maneuver into position to protect Iraqi oil fields near the Kuwaiti border. The crash did not appear to involve hostile fire.
Units of the U.S. 1st Marine Division and British Royal Marine commandos crossed the border into Iraq from the south Thursday afternoon, and Kuwait's official news agency said they captured the border town of Umm al Qasr, a main Iraqi seaport about 30 miles south of the city of Basra. Iraq denied it. There was no confirmation from the United States or Britain.
During the encounter, 15,000 of the 1st Marines engaged the 51st Mechanized Division of the Iraqi army. No U.S. casualties were reported.
High-ranking Iraqi commanders deserted their troops, Marine sources said, and U.S. troops encircled the Iraqis.
The Marines entered Iraq earlier than planned because Iraqi forces were beginning to ignite oil wells. The U.S. troops secured dozens of wells, but some burned because the Marines had no firefighting equipment.
British military spokesmen, meanwhile, confirmed that their forces were now in control of the Al Faw peninsula to the east, which controls a key Iraqi oil-export route. Reports from London indicated that scores of Iraqi troops had surrendered.
This meant the invasion of Iraq was proceeding on several flanks. The British forces entering from the east were headed for Basra and expected to seize the city as early as tonight, while the U.S. Army's 3rd Infantry Division and the 1st Marines were heading to Baghdad and securing oil fields along the way.
Other special forces were reported to be operating in western Iraq, where the capture of a large air base was a top priority.
Missiles and bombs struck Hussein's presidential compound in Baghdad, which the Iraqi president rarely uses. But several of the government departments at the center of his regime are headquartered on the grounds of the complex. They include the Planning Ministry, which erupted into flames.
Reports in Baghdad said one of the buildings hit was the home of Tarik Aziz, the Iraqi deputy prime minister and one of Hussein's most influential and longtime allies.
A government spokesman said at least one person died in the bombing, but he did not say whether the casualty was an Iraqi official. The bombing occurred in an area from which Iraqi citizens and foreign reporters were barred.
Iraqi radio confirmed that the first wave of bombing in the war, which came at dawn Thursday, struck "the home of the family of President Saddam Hussein and the home of the co-fighter Um Uday [Hussein's wife] and the houses of his two daughters."
Iraqi television, owned by one of Hussein's sons, aired what it said was a speech delivered by Hussein after the bombing, in which he wore a military uniform, black beret and eyeglasses. U.S. intelligence officials sought to determine whether the speaker actually was Hussein or whether he had been killed.
The state-run television rejected any suggestion that Hussein did not make the speech.
Asked in Washington if Hussein was dead and the broadcast had shown a look-alike, Rumsfeld said, "There is a debate about that."
Either way, Rumsfeld said, "His days are numbered."
Other targets in the initial phase of bombing appeared to be a military complex south of Baghdad and a power plant in the area.
After the second wave of missile and bombing attacks, the streets of Baghdad were empty. Two tanks were parked a few blocks from the Al-Rashid Hotel. There were no large concentrations of troops.
The few troops in evidence appeared to be deployed to prevent civil unrest rather than to fight any invading forces.
They included volunteers, activists in Hussein's ruling Baath Party, police officers and some soldiers. Three or four gathered about every 50 yards, at street corners and sandbag bunkers, armed with light weapons.
To the south near the border with Kuwait, the Iraqis fired at least five missiles at U.S. encampments Thursday.
The weapons either fell harmlessly in the desert or were shot down before reaching their targets.
U.S. Patriot missile batteries destroyed two of the Iraqi missiles near Camp Thunder, an American base west of Kuwait City, two senior commanders said. No damage or injuries were reported.
Five Patriot missiles were fired from Camp Thunder and nearby Ali Al Salem air base, where U.S. forces are stationed, the commanders said. Two of them destroyed incoming missiles launched from just outside Basra. Two Patriots landed in uninhabited desert. One malfunctioned and self-destructed, as designed, to avoid a harmful explosion.
In Washington, Rumsfeld said the Iraqis were believed to have set fire to three or four wells in the Ramallah oil fields, about 50 miles southwest of Basra and about two miles north of the Kuwaiti border.
A senior defense official said the Pentagon had photos of the fires.
The official said Thursday's air attacks included bombs and ship-launched Tomahawk cruise missiles.
Even though the attack was only "preparing the battlefield," the official said, "occasionally you want to remind them that the attack can come any time. You just want to get their nerves tight."
Causing the jitters, he said, was part of "a very, very robust 'psy-ops' campaign. The message continues to be to surrender. Combat is our last choice, and if you can tip the balance without a full-scale operation, don't you owe it to your country to do that?"
Late Thursday, the official said, military intelligence was beginning to detect some signs of disarray in Iraqi military ranks. He offered no details.
As the fighting went on, the Turkish parliament opened that nation's airspace to U.S. warplanes, ending months of debate over Turkey's role in war against its neighbor.
Parliament also authorized thousands of Turkish troops to enter Kurdish-controlled northern Iraq to protect Turkey's interests there.
The beginning of hostilities provoked scattered street protests in the Turkish capital, Ankara, where antiwar sentiment among the mostly Muslim populace has limited Turkey's cooperation with the Pentagon.
The Turkish parliament has refused to allow deployment of U.S. troops in Turkey for a ground assault on Iraq.
In London, Prime Minister Tony Blair told his nation that British troops were participating in the war. Speaking from 10 Downing Street, he said, "Britain has never been a nation to hide at the back."
He vowed that Iraq's "barbarous rulers" would be overthrown and its people freed.
The speech included some soaring rhetoric. But aware that he was facing an electorate still leaning against the war -- and that the streets were filling with antiwar demonstrations -- Blair stuck mostly to straightforward language.
"The point of the calls," Press Secretary Ari Fleischer said, "is to touch base with world leaders about the military operation, to talk to them about the purpose of the mission."
After meeting with his top military advisors and having lunch with Vice President Dick Cheney, the president convened his Cabinet, Fleischer said, in part to remind its members to press ahead with his domestic agenda despite the war.
Fleischer reiterated Bush's message over the last several days to Hussein's generals: Disobey their leader's orders and lay down their arms.
In the Senate, Democratic and Republican lawmakers set aside earlier differences over war with Iraq and approved a resolution expressing support for U.S. troops and the president.
The resolution was approved 99 to 0. The House was expected to pass a similar resolution.
Meanwhile, the House approved an $835-million measure providing tax relief for members of the military and their families. The bill, expected to win Senate passage soon, would ease tax burdens for families of troops killed in the line of duty.
It also would grant a capital-gains tax break for military personnel who sell their homes and increase deductions for travel by National Guard members and reservists.
Bush authorized up to $22 million in assistance for refugees fleeing Iraq. He said the money could go to international governmental and nongovernmental groups.
U.N. Secretary-General Kofi Annan has said the United States bears "primary responsibility" for humanitarian assistance both during and after the war.
Daniszewski reported from Baghdad and Perry from the Kuwait-Iraq border. Contributing to this report were staff writer Richard Boudreaux and special correspondent Amberin Zaman in Ankara; staff writers Alissa J. Rubin on the Jordan-Iraq border; Edwin Chen, Esther Schrader, John Hendren, Janet Hook and Richard Simon in Washington; and special correspondent William Wallace in London.