(Updates with clashes in San Pedro Sula, Micheletti quote)

TEGUCIGALPA, Aug 12 (Reuters) - Supporters of ousted Honduran President Manuel Zelaya clashed with soldiers and police for a second day on Wednesday as street protests over the June 28 army coup turned rowdy.

Security forces fired tear gas to disperse a crowd of thousands of demonstrators in the capital Tegucigalpa and protesters responded by throwing stones in a scuffle near Congress. The demonstration calmed down by the afternoon.

Zelaya's wife attended another pro-Zelaya protest on Wednesday in the industrial city of San Pedro Sula near the country's Caribbean coast, which was also broken up by police firing tear gas canisters .

Zelaya's overthrow, after opponents accused him of trying to change the constitution to allow presidential re-election, has thrust Honduras into the worst political crisis Central America has seen in years.

Talks to resolve the standoff, mediated by Costa Rican President Oscar Arias, have so far made little progress as a de facto government headed by former Congress head Roberto Micheletti refuses to let Zelaya return to power, despite widespread international condemnation of the coup.

Protests on Tuesday and Wednesday by pro-Zelaya activists left broken windows at shops and fast-food restaurants and sent demonstrators fleeing clouds of tear gas. It was one of the few times the near-daily rallies have turned violent since the coup.

Micheletti, in a message broadcast on national television, claimed the clashes were being spurred by "foreign agitators" and promised to respect the rights of those detained at the protests.

"We have to stop with firmness any criminal acts to avoid property damage to small and medium-sized businesses, which is putting many Hondurans out of work," Micheletti said.

The June 28 coup was bloodless and since then only two protesters have been killed in demonstrations. One was shot by soldiers at the airport when Zelaya tried to return in a plane and was blocked by the army. The other was shot in the head in a later protest.

Zelaya, an ally of socialist Venezuelan President Hugo Chavez, has been touring the Americas in exile as most of the world pushes for his return and supporters hold continual street rallies. Thousands have also turned out to support Micheletti's de facto government.

President Barack Obama said this week the United States strongly condemned the coup but it was hypocritical for critics to demand a more forceful U.S. role in bringing Zelaya back.

The interim leaders have said they are ready to hold on to power until regularly scheduled elections in November, even though the head of the Organization of American States has said the regional body will not recognize the result. (Reporting by Fabian Cambero; Writing by Mica Rosenberg; editing by Todd Eastham)