[This story was updated on 04.01.03 at 9:06 p.m. ET.]
In what some officials are calling the beginning of the battle for Baghdad, coalition forces engaged in major combat with Iraq's elite Republican Guard about 60 miles southwest of the Iraqi capital early Wednesday local time on day 14 of Operation Iraqi Freedom.
The "big battle," as a U.S. military official described it to NBC News, came after Tuesday's intense bombing of the region in and around the town of Karbala, where Saddam Hussein's Medina Division has been resisting coalition forces for several days.
Air attacks late in the day and early Wednesday also hit targets in Baghdad, including a presidential palace, according to CNN.
Coalition forces received a battle plan for a siege on the capital Tuesday, although no timetable for when the ground attack will commence has been established. Gen. Tommy Franks will give the order whenever a "tactical advantage" presents itself, without having to consult first with either President George W. Bush or Defense Secretary Donald Rumsfeld, military officials told CNN.
The new battle plan may cause fighting in Basra, Najaf, Nasiriya and other cities to take second priority. (Click for map of the battlefield.)
Also late Tuesday, coalition forces rescued American POW Jessica Lynch, according to U.S. Central Command. Iraq is still holding six other prisoners, according to the Pentagon.
Meanwhile, the White House continued to question whether Hussein has been killed or injured. Iraqi television networks said he would address his nation on Tuesday, but Iraqi Information Minister Mohammed Saeed al-Sahaf read a statement from the leader instead. In it, Hussein called on the Iraqi people to launch a jihad, or holy war, on coalition forces.
"Where are Iraq's leaders?" Rumsfeld said at his briefing Tuesday. "The night before the ground war began, coalition forces launched a strike on a meeting of Iraq's senior command and control, and they have not been heard from since."
Elsewhere Tuesday, a major firefight involving U.S. Marines and Iraqi forces erupted around Diwaniya, 75 miles southeast of Baghdad. Ninety Iraqis died in the skirmish, and 44 were taken prisoner, according to Fox News.
Coalition forces located Baath Party and military headquarters within the city and found 6,000 mines, a building filled with rocket-propelled grenades and other stockpiles of ammunition.
Farther south, U.S. bombs and missiles hit targets near Basra, destroying a presidential yacht as well as another vessel, according to The Wall Street Journal.
U.S. Brig. Gen. Vincent Brooks said in a Central Command briefing Tuesday that allied forces have not found any evidence of weapons of mass destruction in Iraq, but the Bush administration claims the discovery of stashes of gas masks and plastic suits in military and Baath Party offices means the regime may plan to use chemical weapons in the future.
Other key developments in the last 24 hours:
— Joe D'Angelo, Corey Moss and Ethan Zindler