Protesters have denounced the presidential poll as rigged [Reuters]

Protesters in Haiti, angry at the results of the recent elections, have set fire to the main offices of the ruling party and manned barricades in the capital, Port-au-Prince.

The demonstrators took to the streets on Wednesday after officials had announced that Jude Celestin, representing the ruling party, will stand in the upcoming presidential runoff vote.

Michel "Sweet Micky" Martelly, a popular singer, had trailed Celestin by about 6,800 votes - less than one per cent, according to the preliminary results released by Haiti's Provisional Electoral Council.

Martelly supporters set up barricades near the Petionville restaurant where the tallies were announced and threw rocks at people passing nearby. Gunshots were also heard.

"If they don't give us Martelly and [Mirlande] Manigat [in the second round], Haiti will be on fire," Erick Jean, a protester, said.

"We're still living under tents and Celestin wastes money on election posters.''

Violence was also reported in Cap-Haitien as well as the southern city of Les Cayes, where residents said government buildings had been attacked and set on fire.

Results questioned

Mirlande Manigat, the former first lady, will advance to the runoff and stand against Celestin, after no candidate gained more than the 50 per cent required to win in the first round.

The results announced late on Tuesday were immediately questioned in Haiti and abroad.

Much of the concern centred around conflicts between the announced results and those reported recently by the National Observation Council, a local election monitoring group financed by the European Union, which said that Celestin would be eliminated.

The US embassy said in an e-mailed statement: "The Government of the United States is concerned by the Provisional Electoral Council's announcement of preliminary results ... that are inconsistent with the published results of the National Election Observation Council'' as well as US observers and vote counts by domestic and international observers".

Official election observers have said a third candidate might be included in the January 16 runoff if the electoral council decides the first-round vote was close enough, even if the constitutionality of such a move is debatable.