PORT-AU-PRINCE, Haiti (AP) _ Four assailants, including two in army uniforms, opened fire Thursday on a meeting of the governing Council of State, killing a union activist and wounding two politicians, witnesses said.

The attack occurred in a hotel courtyard where the 19-member council was meeting with union, political and business leaders to deal with a wave of violent crime.

The attackers burst into the courtyard and sprayed the group with M-16 rifle fire, according to witnesses and independent radio reports.

Two of the gunmen wore army uniforms, while the other two were in civilian clothes, the reports said.

About a half-hour later, a truckload of soldiers arrived at the hotel, in a mainly residential area of Port-au-Prince.

The civilian council governs alongside President Ertha Pascal-Trouillot. She was not present at the meeting.

''The provisional government regrets and condemns in the strongest terms this morning's events,'' the Information Ministry said in a statement.

The Congress of Democratic Movements, a Socialist political alliance, said the attack was an attempt to derail the fragile civilian government's plan to hold presidential elections in September.

The U.S. Embassy said it ''condemns in the strongest possible terms the shooting at the Hotel Santos. ... This act of barbarism represents an attack against the entire democratic process and against the aspirations of the Haitian people for secure and free elections.''

Witnesses and Radio Antilles identified the dead man as union activist Jean-Marie Montes.

Council member Serge Villard was wounded in the stomach and Emmanuel Mani, a member of the Socialist National Progressive Party, was wounded in the thigh, reports said. Both were hospitalized.

Radio Soleil, a Roman Catholic station, quoted an unidentified bystander as saying the attackers may have mistaken Villard for Council president Dr. Louis Roy. The bystander said one soldier asked him if he knew Roy, and he told him he did not.

Both Roy and Villard are white-haired, light-skinned and in their 70s. Roy was inside the hotel at the time. Windows were shattered by bullets.

Roy, one of the authors of Haiti's 1987 constitution and a founder of the Haitian Red Cross, said later on Radio Metropole: ''I might be killed, but the struggle will go on.''

The apparent involvement of soldiers raised concerns about the army's intentions as Haiti moves toward what would be its first democratically elected government since independence from France in 1804.

''It is horrible,'' said Rene Theodore, leader of the Haitian Communist Party. ''It doesn't seem the government can cope with the situation ... If the problem is not resolved, it is difficult to hold elections with serenity.''

Haiti's last independently run elections, on Nov. 29, 1987, were aborted when thugs supported by the army shot and hacked to death at least 34 voters at polling stations.

The Army High Command pledged to support Mrs. Pascal-Trouillot, appointed in March to replace Lt. Gen. Prosper Avril, who fled into exile after protests against his military government.

But skeptics have questioned the willingness of the ill-disciplined and corrupt force to relinquish privileges gained over many years.

Many have asked why security forces have not done more to try to stop the crime wave, in which 13 people have been killed in Port-au-Prince since Tuesday.

The president and the Council of State, which has veto power over her decisions, have been in a dispute over her appointment of Marie Violene Legangneur as finance minister.

Council members regard Legangneur as a sympathizer of the 29-year dictatorship of Jean-Claude ''Baby Doc'' Duvalier, who fled into exile in 1986, and of his late father, Francois ''Papa Doc.''

The council says it will not approve any electoral law signed by the finance minister. The law is necessary to hold elections.

Haiti, the first republic of former slaves, gained independence from France in 1804 and has been governed mostly by repressive military rulers.