Port-au-Prince, Haiti ? Militants crushed a rally against Haiti’s president before it began Thursday, setting up flaming barricades along the route of a protest march and hurling stones as demonstrators tried to gather in the capital.

Opposition leaders accused President Jean-Bertrand Aristide of orchestrating the suppression, but the United States said it was standing by him as he confronts an armed rebellion affecting a dozen provincial towns.

“The policy of the administration is not regime change,” Secretary of State Colin Powell told the U.S. Senate Foreign Relations Committee. “President Aristide is the elected president of Haiti.”

A week of violence has killed 49 people and blocked food and fuel supplies to northern Haiti.

In the capital Port-au-Prince, which is in the south and has not been affected by the uprising, about 100 Aristide supporters began lobbing rocks as protesters tried to gather. Protest organizers said one person was hit by a bullet and three were injured by rocks.

Police retreated to their station when the protesters were attacked, offering no protection.

Critics at home and abroad, including the U.S. government, have accused Aristide of blocking similar demonstrations by allowing police and supporters to attack opponents — charges the Haitian president denies.

“Aristide has confirmed he is a delinquent outlaw president,” one opposition leader, Evans Paul, said.