JIM LEHRER: This was the day Iraq's government formally took back control of its cities. U.S. combat troops pulled back in a move met with widespread celebration and also new violence.
Judy Woodruff has our lead story report.
JUDY WOODRUFF: Iraqi troops marked the occasion with a parade in Baghdad. It was their first full day of control of the nation's cities since the U.S. invasion in 2003.
Prime Minister Nouri al-Maliki declared a public holiday, proclaiming it National Sovereignty Day, and the celebrations by ordinary Iraqis overflowed into the streets.
AHMED ALI, Baghdad resident (through translator): We congratulate the Iraqi people about the U.S. pullback from urban cities. And we hope for the full U.S. withdrawal from Iraq, God willing, wishing for safety and security for the Iraqi people.
JUDY WOODRUFF: But to the north, a car bomb in Kirkuk tore through a crowded market, killing at least 33 Iraqis and wounding scores more. It was the latest in a string of attacks nationwide, killing more than 250 people in just over a week.
And the U.S. military announced four more U.S. soldiers died in combat today; that made 15 Americans killed this month and more than 4,320 since the war began.
Still, the top U.S. commander in Iraq, Army General Ray Odierno, said violence has fallen to the levels of 2003. And he said he's hopeful that Iraq will be in good hands with today's transition.
GEN. RAY ODIERNO, commander, multinational forces in Iraq: ... we've seen Iraqi army grow professionally. We've seen them conduct operations across the country in a nonsectarian way.
And, frankly, the biggest improvement of any force here in the last two years has been in the national police. They are seen as a legitimate, credible force that conducts nonsectarian operations around Iraq.
So I feel fairly confident in that. The local police is the one we probably worry about the most, and that's why we haven't turned over security yet to the local police.
JUDY WOODRUFF: A hundred and thirty thousand American troops will stay in Iraq for now. Combat units will return to the cities only if the Iraqi government seeks their help. Otherwise, they'll continue operations in rural towns and along the border and help with training and intelligence. All U.S. forces are due to leave Iraq by the end of 2011.
But leaders on both sides have warned of more attacks in the meantime. President Obama said it again today in Washington.
BARACK OBAMA, President of the United States: Now, make no mistake: There will be difficult days ahead. We know that the violence in Iraq will continue. We see that already in the senseless bombing in Kirkuk earlier today.
And there are those who will test Iraq's security forces and the resolve of the Iraqi people through more sectarian bombings and the murder of innocent civilians. But I'm confident that those forces will fail.
JUDY WOODRUFF: The Iraqi government faces other challenges, as well. It suffered a setback today in the first international bidding to develop Iraqi oil fields in more than 30 years. Foreign companies demanded much higher fees than the government was willing to pay, and only one field was awarded.