BAGHDAD, Iraq -- With Iraqi forces routed in Baghdad, U.S. military commanders may soon be shifting the focus of the war to Saddam Hussein's hometown, Tikrit.

A sprawling city north of the capital, Tikrit is host to an army garrison for the Republican Guard.

Brig. Gen. Vincent Brooks, a Central Command spokesman, said Wednesday that coalition forces are already hitting "command and control" facilities in the city. Brooks said neutralizing Tikrit is an important step in defeating the Iraqi regime.

Some Kurdish leaders are claiming that Saddam, his two sons, and top aides already went into hiding in Tikrit. But that hasn't been confirmed, and many believe the Iraqi leader and his sons were killed in Monday's U.S. airstrike in a Baghdad residential area.

Meanwhile, Central Command is still investigating if Monday's crash of an American fighter jet near Tikrit was due to hostile fire.

'The Game Is Over,' Iraqi Envoy To U.N. Says

Iraq's U.N. ambassador said Wednesday "the game is over" and clarified that he means the war is over.

It is the first admission by an Iraqi official that U.S.-led coalition troops have overwhelmed Iraqi forces.

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Mohammed Al-Douri said his hope now is that the Iraqi people will be able to live in peace.

"The game is over, and I hope the peace will prevail," he told reporters in New York. "I hope the Iraqi people will have a happy life."

Al-Douri said that because of the war, he hasn't had any communications with Iraqi officials for a long time.

U.S. officials, although optimistic about the celebratory scenes from Baghdad, repeated often that the war has not ended yet and tough fighting lies ahead.

"The war is not over," White House spokesman Ari Fleischer said. "We still have armed forces in harm's way.

"The president is aware there are cities in the north that are not like cities in the south," he said. "There are still pockets of resistance."

Defense Secretary Donald Rumsfeld warned of "tough fighting ahead, despite all the celebration."

"Other Iraqi cities are still being contested," even though the capital was not, he said.

Earlier, as scenes of celebration unfolded in Baghdad and other Iraqi cities at the apparent loss of power of Saddam's regime, Rumsfeld said Americans share in the joy of the those who now are free.

"Anyone seeing the faces of liberated Iraqis has to say this is a very good day," Rumsfeld told reporters at the Pentagon on Wednesday. "We said from the beginning he was finished. Now they are daring to believe it."

The Pentagon chief didn't go so far as to say the regime is finished in Iraq, but he did say it was losing power rapidly. And, he added, Saddam has taken his "rightful place" with failed dictators such as Hitler and Stalin.

Rumsfeld compared the celebrations of Baghdad residents and the toppling of statues of Saddam Hussein with the fall of the Berlin Wall. He said the effect of these "breathtaking" sights has been felt in the United States, where a large crowd of Iraqi Americans turned out for a rally in suburban Detroit. (Full Story.)

"We're seeing history unfold -- events that will shape the history of the nation .. and perhaps the region," Rumsfeld said. "To the families of those who lost loved ones, let me say this: As you watch the historic scenes unfold, take immense pride in the sacrifice of your loved ones. They made this happen."

As Rumsfeld fielded questions from Pentagon reporters, Rumsfeld answered "don't know" to questions about whether Saddam was dead or alive, or if he was in the bombed building.

"He's either dead, or he's incapacitated, or he's healthy and cowering in some tunnel someplace trying to avoid being caught," Rumsfeld said. "He's not been around. He's not been active."

He said planes carrying humanitarian relief to Iraqi civilians already have begun to land at Baghdad's airport.

Hours earlier, U.S. tanks and armored personnel carriers settled in the heart of Baghdad after Marines secured a city square on the east bank of the Tigris River.

Troops waved to crowds of bystanders, who waved back.

A military official at Central Command in Qatar said U.S. commanders were "heartened" by the welcome that Baghdad residents are giving U.S. troops. He said his colleagues are feeling a "sense of warmth."

A crowd of Baghdad residents danced on the remains of a statue of Saddam in Firdos Square after a Marine tank helped pull it down. (Full Story.)

But despite the street celebrations in parts of Baghdad, sporadic resistance -- mainly from snipers -- remains.

U.S. Marine and Army units are facing sniper fire from roving bands of enemy fighters in the Iraqi capital. TV footage shows heavy gunfire and buildings apparently on fire near Baghdad University. Thick, black smoke rose into the air.

Central Command is reacting cautiously to the celebrations in Baghdad. Looting has broken out in the Iraqi capital as residents cheer U.S. forces.

U.S. troops are sweeping through the city, seizing or destroying buildings that once housed some of Saddam's most feared security forces.

Elsewhere in the capital, U.S. forces are expanding their reach. They've secured a military airfield, captured a prison and set fire to a Republican Guard barracks. A Marine officer said the house of Saddam's son Uday was on fire, apparently hit by a bomb.

U.S. commanders declared that Saddam's regime has lost its grip on Baghdad.

At the daily war briefing at Central Command headquarters, Brig. Gen. Vincent Brooks said the Iraqi capital is "now one of those areas that has been added to the list of where the regime does not have control."

Report: Kurdish-U.S. Forces Seize Key Hill Near Mosul

A Kurdish leader said his forces and U.S. troops are pressing forward in northern Iraq, seizing control of a key hill near Mosul.

The area had been heavily defended by Iraqi forces and served as a hub for air defenses against coalition airstrikes. It also served as a munitions center.

Although Iraqi forces still hold the city, the Kurdish leader said taking the hill shows the crumbling of the enemy's northern front and means no Iraqi defenses remain between Kurdish-U.S. forces and Mosul.

It also will allow passage for people wishing to escape the embattled city and possibly a way in if coalition forces mount a ground assault.

Kurdish forces have also tightened their ring around the key oil center of Kirkuk.

Earlier, in nearby Irbil, a huge street party broke out as word filtered up that Saddam's regime appeared to have lost its grip on Baghdad.

In the Kurdish city, people were dancing in the streets, kissing one another and waving Kurdish and American flags. Motorists honked their car horns, and local shops blared music.

An Associated Press reporter at the scene said he saw some U.S.-allied Kurdish fighters joining the celebration as they drove by in armored troop carriers and pickup trucks. He said they're waving the "V" for victory sign, and one fighter had a small U.S. flag wrapped around the muzzle of his rifle.

Unlike in Baghdad, there has been no sign of mass looting in Irbil. The AP reporter said the Kurdish city has had a relatively strong economy and a strong civil administration.

Celebrations Turn To Looting

Looting has taken place in several Iraqi cities. An American commander in Qatar said coalition troops are trying to discourage it.

Earlier, an elderly man in Baghdad held up a poster of Saddam and beat it with his shoe. A younger man spit on the portrait, while several others kicked at the face of the Iraqi president, whose fate remains unclear.

Iraqi government and military authority seemed all but gone.

One of the men defacing the Saddam poster said, "Come see, this is freedom. This is the criminal, this is the infidel.

"This is the destiny of every traitor. He killed millions of us," he said.

Teenage boys were walking the streets, some holding assault rifles. Gunshots were sending motorists and pedestrians rushing in all directions. One man carrying a rifle yelled, "We are with the U.S."

Some looters came with wheelbarrows and pushcarts. Others were loading stolen items into car trunks. Looters at government and military buildings, the Olympic headquarters, a state-owned oil company and a police building made off with computers, bookshelves, tables -- even Iraqi jeeps.

Gangs of youths and middle-age men were looting warehouses of the Trade Ministry, coming out with air conditioners, ceiling fans, refrigerators and TV sets.

Hundreds of Iraqis cheered U.S. troops in Saddam City, a poor neighborhood in northeast Baghdad. One shouted, "Thank you, thank you, Mr. Bush!" One group of Iraqis held up a portrait of Saddam Hussein and smashed it, calling him a "criminal."

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