Castro (pictured right), the wife of ousted former leader Manuel Zelaya, led thousands of supporters through the streets of the capital, Tegucigalpa, to protest the result of the election. Zelaya was also present (center).

The demonstration was said to have attracted more than 5,000 supporters, who gathered outside the office of the Supreme Electoral Court.

Also at the forefront of the march were supporters who bore the coffin of a slain party activist amid chants of "murderers and fraud."

"We are here to denounce the culture of death promoted since the coup, this can only be a political crime," said Zelaya, whose removal from office in a coup in 2009 has divided the country.

The head of the electoral court last Wednesday declared Juan Orlando Hernandez, of the ruling National Party, the winner. Hernandez had 36.8 percent of the vote, while Castro - who had initially declared herself the winner - had 28.8 percent.

Zelaya said he would file a formal complaint with the tribunal on Monday. "If the vote recount is not done by Friday, the legal deadline, we will legally challenge the election," Zelaya said.

"If they do not accept our complaint, we will go to the courts, and if the courts don't take our case, we will go to international bodies," Zelaya added.

'Robbed of the presidency'

Castro - who has called the election "a disgusting monstrosity that has robbed me of the presidency" - has alleged that tally sheets were altered, with dead or absent people included on the register of voters. She also claims that monitoring of polling stations was inadequate and allowed for election fraud.

Hernandez claims his victory is legitimate and has said he is not prepared to negotiate.

Castro, whose Libre Party proposes "Honduran-style democratic socialism," has said she would rewrite the constitution and "re-found" the poverty and crime-stricken country. A similar move was made by Zelaya's government, prior to the coup that toppled him.

The country of 8.5 million people has a homicide rate of some 20 murders per day, with 71 percent of the population living in poverty.

The dead activist, Jose Ardon, was kidnapped late on Saturday and later shot and killed. Ardon was a member of "the motorcyclists," motorbike riders who have led support marches for Zelaya and his wife since the coup.

rc/lw (AP, AFP, dpa, Reuters)