MANAGUA : Nicaragua's ruling Sandinistas were set to rally in the streets Friday after the Supreme Electoral Council said they held sway in more than two-thirds of local elections -- results the opposition says are marred by fraud.

In a development likely to fuel tensions already running high, the electoral council announced late Thursday candidates backed by leftist President Daniel Ortega won in more than two-thirds of mayoral races in the November 9 election.

According to the council, the final authority on vote matters, leftist Sandinista candidates won in 105 of the 146 races in dispute, including the biggest prize, Managua, as well as most of the country's largest cities.

Liberal opposition members however charge that voter fraud was widespread; they want the legislature to strike down the election results.

Since before the vote even took place, Sandinista supporters have been in the streets.

Many pro-Sandinista activists have taken to the streets toting home-made mortars and clubs in what opponents charge is a bid to deter Ortega foes from demonstrating against the alleged fraud in the poorest Central American nation.

The United Nations, European Union and United States and several Nicaraguan NGOs have expressed concern about the level of transparency in the voting, increasingly seen as a referendum on the performance of Ortega, 63, a former rebel and close ally of communist Cuba and President Hugo Chavez of Venezuela.

"Nobody is the winner with what has happened here. Not Nicaragua, not Central America," a European diplomat told AFP privately, warning: "This is potentially dangerous ... and the international community's influence is limited."

Government backers have been on the streets around the clock at about a dozen traffic circles in Managua, waving support signs and others calling for peace, with salsa music blaring.

Sandinistas were called to celebrate later in Revolution Square home to the tomb of the Sandinistas' founder Carlos Fonseca.

On Wednesday opponents of the Sandinistas said they had enough votes in Congress to annul the election -- a notion dismissed by Supreme Court Justice Rafael Solis, who said Congress had no such authority.

The opposition has "incontrovertible proof of clumsy, shameless and massive fraud" carried out by the Electoral Council in coordination with the Sandinistas, said former president Arnoldo Aleman, who heads the right-wing Liberals.

It is the third time the Sandinistas have won Managua, where the mayor-elect is former boxing champ Alexis Arguello.

- AFP