It said most of the rebels in the barracks were captured, but some fled and left behind their uniforms and weapons. The communique did not say how many rebels were captured or had escaped. The normal force of the Dessalines Barracks is 750 soldiers.
Loyal soldiers shelled the barracks Friday night and resumed the artillery bombardment Saturday. There were firefights in the area of the barracks, which adjoin the National Palace in the center of Port-au-Prince. Official casualty figures were not available.
A source close to the government said 17 soldiers, all thought to be rebels, were killed in Friday's fighting. Haitians monitoring military radio broadcasts said reports indicated the Presidential Guard suffered 15 casualties but there was no breakdown of dead and wounded.
Port-au-Prince remained calm after the government claimed victory.
Its communique said the captured rebels implicated drug traffickers in efforts to overthrow Avril that began April 2 with an attempted coup. It said an anti-government plot was organized by Haitian exiles formerly associated with the ousted regime of dictator Jean-Claude Duvalier.
The statement also claimed the mastermind of the revolt was former Interior Minister Roger Lafontant, who is now living in the Dominican Republic, which shares the island of Hispaniola with Haiti.
The statement was issued at 3:15 p.m. MDT after several hours of heavy shelling of the barracks. Shooting had tapered off shortly before the announcement.
U.S. officials said earlier that a hole was blown in the roof of the gleaming white National Palace, which serves as the presidential residence.
The rebels accuse Avril's government, which took power in a military coup six months ago, of favoritism toward the Presidential Guard in pay and living conditions. They also said the government was arbitrarily dismissing senior officers in a U.S.-supported crackdown on drugs and corruption.
Avril, 50, came to power in September 1988 in a coup by non-commissioned officers that ousted Lt. Gen. Henri Namphy. The officers demanded democratic reform and an end to state-sponsored violence.
Namphy had deposed a short-lived civilian government. He had earlier led a junta that took over after Jean-Claude Duvalier was swept from power in a popular uprising and fled to France in February 1986.