......................................................................... (AP) _ Brig. Gen. Prosper Avril declared himself leader of Haiti Sunday after ousting Lt. Gen. Henri Namphy in a military coup. Residents reported hours of gunfire Saturday near the presidential palace.

In an address on national television at 2:30 a.m. EDT, Avril said the presidential guard he commanded had toppled Namphy Saturday because it was ''sickened'' by the way Haiti had been governed.

Avril, a former adviser to President Jean-Claude Duvalier, said Haiti will respect all international treaties, liberties and human rights and said that ''dialogue will be honored for the sake of national reconciliation.''

Namphy was arrested and escorted under guard to the international airport late Saturday, a government spokesman said.

The Dominican Republic announced Namphy and Port-au-Prince Mayor Franck Romain had requested and been granted political asylum in its Port-au-Prince embassy. It said they were in the embassy and would be flown on a military plane to the capital of Santo Domingo Sunday.

The reports on Namphy's whereabouts could not be independently confirmed early Sunday.

The government reported Namphy's ouster several hours after shooting broke out at the main plaza in front of the presidential palace. The gunshots sent dozens of people fleeing for cover in what appeared to be fighting between army factions, witnesses said.

Earlier, Frantz Lubin, Haiti's director of information, had told The Associated Press soldiers were reportedly slain during the coup, but no casualties were mentioned by Avril.

Rapid gunfire continued until about 11:45 p.m. Saturday.

Avril has been a key figure in Haiti's succession of governments since Duvalier fled to exile in France on Feb. 7, 1986.

He served as an adviser to a military-civilian junta headed by Namphy which succeeded Duvalier. Avril was forced to resign that post in early 1986 by anti-government demonstrations.

He then participated in the June 19 coup that toppled the 4-month-old civilian government of President Leslie Manigat, who had tried to transfer Avril from commander of the presidential guard to an administrative post.

In his speech at the national palace, Avril promoted himself to lieutenant general and said he had been forced to act.

Speaking from the national palace before the presidential guard, Avril said: ''The presidential guard, sickened by the way the country has been governed since the 7th of February, 1988 ... has been forced to act again.''

Manigat was named president Feb. 7, 1988.

Earlier, Frantz Lubin, Haiti's director of information, had told The Associated Press that Dessalines Barracks Commander Jean-Claude Paul had been named the new commander-in-chief of the army, but Paul was not mentioned during the address.

Behind Namphy, Paul was considered the most powerful figure in the military regime.

Avril, a bespectacled, slim man of medium height, was dressed in uniform during his address. He was introduced as ''the most honest officer in the armed forces'' by Sgt. Joseph Heubreux, who wore full battle gear.

He reference to ''dialogue'' followed a similar proposal by opposition leader Marc Bazin. Bazin, a conservative leader of the Committee for Democratic Understanding, recently said the democratic opposition and military government should meet. Bazin was one of four leading candidates for president in the aborted Nov. 29 civilian-run national elections.

A U.S. Embassy spokeswoman, Susan Clyde, said early Sunday that the new government made initial contacts with U.S. officials.

''The stated intentions of this new government ... were to correct the abuses of the Namphy era, and to try to re-launch a period of change and progress for Haiti,'' she said. ''And obviously we hope that the government will be able to carry out these intentions.''

A usually reliable source, speaking on condition of anonymity, said an army major told him that a group of officers detained Namphy after preventing him from entering the palace at 4:30 p.m.

Sources said the fighting involved army factions and members of the Tonton Macoutes, dreaded agents that terrorized Haitians during the 29-year-old dictatorships of the Duvalier family.

A French diplomat who spoke on condition of anonymity and Radio Metropole said the shooting, including automatic gunfire, broke out around 5 p.m. Satuday on the Champ-de-Mars Plaza, in front of the Presidential Palace and near the army general headquarters and Dessalines Barracks.

Several dozen panicked people were seen running away from the plaza.

The coup came six days after about 20 thugs invaded the St. Jean Bosco Roman Catholic church during a Mass being said by the Rev. Jean Bertrand Aristide, a critic of the military government.

The thugs, armed with guns, machetes and knifes, killed 13 people and wounded 77 and then set fire to the church as soldiers watched from across the street.

That night, five men and a woman boasted on government television that they took part in the massacre and on Monday thugs burned down a second Catholic church.

Some people in the St. Jean Bosco church during the attack said they recognized several City Hall employees among the assailants.

Namphy's government said it ''regretted'' the killings. It has made similar statements after earlier killings but no arrests were announced.