PORT-AU-PRINCE, Haiti (AP) _ With doves and balloons filling the air and Jean-Bertrand Aristide at his side, President Clinton declared the U.S. mission to Haiti a ``triumph of freedom over fear'' Friday and turned over peacekeeping duties to the United Nations.

``We celebrate the restoration of democracy to your country,'' Clinton told thousands of cheering Haitians at the National Palace, six months after U.S. forces peacefully occupied the Caribbean nation to oust the military leaders. ``Never again must it be stolen away.''

In a nine-hour visit, Clinton also met with U.S. troops, many soon to return home, and pronounced the U.S.-led military mission to restore Aristide to power a success.

Clinton received a hero's welcome in the Haitian capital. The government pronounced the day a national holiday _ Clinton Day _ and thousands of Haitians thronged the palace grounds for Clinton's speech.

The festivities were clouded by new allegations suggesting a link between a senior member of Aristide's government and a political assassination plot.

But Clinton lavished praise on the 41-year-old Catholic priest-turned-politician who was elected in 1990, ousted by the Haitian military in 1991 and returned to power last Oct. 15.

``His strength in the face of great challenge reflects the unbreakable will of the Haitian people,'' Clinton said, speaking under a hot, hazy blue tropical sky.

For his part, Aristide _ who has denied any wrongdoing by the Cabinet member _ returned the praise, crediting Clinton for helping Haiti to move ``from death to life.'' He also expressed gratitude to the U.S. troops ``who helped restore democracy to our country.''

Despite the reduced role of the United States, Clinton vowed to continue to help Haiti complete national recovery and help it prepare for its June 4 legislative elections.

But in a concession to the difficulties still faced in the impoverished nation with a long history of violence, Clinton conceded: ``The path ahead will not be easy. ... Justice does not bloom overnight.''

The visit _ the first by a U.S. president since Franklin Roosevelt came here 60 years ago _ gave Clinton a chance to savor the fruits of his boldest foreign policy gamble.

At ``Warrior Base Haiti,'' a makeshift military encampment that houses 1,700 troops, Clinton stood against a backdrop of military equipment and camouflage netting and told American forces, many of them soon to be headed for home:

``Thank you for being democracy's warriors. Thank you for helping to bring back the promise of liberty to this long-troubled land.''

Then, coatless under a broiling sun, he plunged into the crowd and pumped hands.

Signature event of the day was a ceremony attended by U.N. Secretary-General Boutros Boutros-Ghali marking the formal transition.

The U.N. chief said the event marked ``a turning point'' even though ``the way ahead will not be easy.''

Clinton declared that the U.S. mission had been accomplished ``on schedule and with remarkable success'' as U.S. and U.N. flags were exchanged and troops paraded before the leaders. Friday's ceremony, he said, was meant ``to celebrate the triumph of freedom over fear.''

Clinton and Aristide met privately in the presidential palace for 20 minutes before public events at the palace.

Madeleine Albright, the U.S. ambassador to the United Nations, said Clinton praised Aristide for seeking FBI help in investigating the killing of an outspoken opponent of his government.

At issue are reports that Aristide's interior minister, Brig. Gen. Mondesir Beaubrun, had been implicated in the plot to kill outspoken opposition leader Mireille Durocher Bertin.

A senior White House official, speaking on condition of anonymity, said Clinton reiterated ``very firmly'' with Aristide the need to thoroughly investigate the assassination.

For his part, Aristide responded with a flat ``no'' when asked by reporters if Beaubrun had been involved in Bertin's murder. He also said he didn't think the new controversy cast a damper over Clinton's visit.

As to help from the FBI, Aristide said, ``We welcome help from the international community and from the United States, which is helping us finding truth about violence ... and we'll be working together.''

Clinton and the Haitian leader discussed the need to build ``an all-inclusive judicial system,'' that will allow Haitians to investigate crimes and lock away criminals, Albright said.

Although there have been up to 22,000 U.S. troops in Haiti, the force now is about 4,000. That number will reduce to about 2,400 after a few months, just under half of the 6,000-strong U.N. peacekeeping force that will remain here until after Aristide's successor takes office.

The task of national recovery for the impoverished Caribbean nation _ the poorest in the Western Hemisphere with a per capita annual income of $265 _ remains incomplete. Political tensions remain high and lawlessness continues.

But on Friday, celebration was clearly the dominant theme during Clinton's nine-hour visit.

His speech to U.S. troops was enthusiastically received. Earlier, he had drawn some criticism for seeing U.S. troops in Kuwait last October but postponing a planned end-of-the-year visit to Haiti.

``This shows us that somebody cares _ that Americans know we're here and they care,'' said one, Eric Roblee of Jacksonville, Fla. ``We don't want to be forgotten.''

Before leaving Haiti, Clinton late Friday returned to the military base for informal chats and a tour of facilities. He watched a group of soldiers playfully bouncing a companion up and down on an oil drum suspended on ropes, quipping, ``That's what I do for a living.'' Then he joined a group shooting baskets _ and sunk one himself on the first try.

Clinton sent troop-filled planes toward Haiti on Sept. 18, 1994, recalling them only after military leaders _ in a last-minute diplomatic deal brokered by former President Carter _ agreed to leave voluntarily. U.S. troops arrived peacefully the following day.

``The moment the military leaders learned that you were on the way, they got out of the way,'' Clinton told the American forces. Plugging his own decision to send in the troops to restore democracy, Clinton recalled that it ``could not be done. And you proved them wrong.''

One of those critics, Senate Majority Leader Bob Dole of Kansas, offered praise of his own to the U.S. troops. ``We all support democracy in Haiti. But that does not mean, however, that we should have occupied Haiti in the first place,'' Dole said in Washington. He also said he was worried ``U.N. bureaucrats'' would steer the peacekeeping force _ and the Americans in it _ into misguided missions, recalling the 1993 missteps in Somalia.

Only one American soldier has been the victim of hostile fire in Haiti.