Rio de Janeiro (AFP) - Brazilian ex-president Luiz Inacio Lula da Silva hinted strongly at seeking a return to power in a fiery speech that dismissed corruption charges against him as persecution.

Lula, who was massively popular when he left office in 2010 and remains a giant of the Latin American left, was campaigning in western Rio de Janeiro on behalf of Jandira Feghali, a communist candidate running for mayor in local elections next Sunday.

But the appearance before some 1,000 excited activists in front of a brick church was far more about Lula's own campaign to make a comeback at the 2018 presidential election.

"You will be my electoral support in 2018," he said to enthusiastic cheers, also vowing "to keep fighting for this country."

A one time barely literate shoeshine boy who founded the Workers' Party or PT and became one of Brazil's most influential presidents, Lula spent much of the half-hour speech recalling his achievements in reducing poverty and expanding education.

"I proved that it's possible for people to change the history of this country," he said. "In Brazil the poor stopped being a problem. The poor became part of the solution."

Lula, 70, was on friendly ground.

The small but impassioned crowd cheered loudly, beat on drums and chanted his name. Supporters lit red flares, engulfing the public square in thick smoke.

- Lula's downfall? -

But these days, Lula needs all the friends he can get.

Federal prosecutors have charged him with taking bribes in a vast embezzlement scheme centered on state oil company Petrobras that they say he oversaw while he was president. A trial could fatally damage his electoral ambitions.

Multiple former allies have already been investigated or indicted in the sprawling probe codenamed Operation Car Wash, the latest being Antonio Palocci, a former finance minister who was arrested earlier Monday. Another former finance minister, Guido Mantega, was detained last Thursday.

And in another blow to Lula's legacy, his handpicked successor Dilma Rousseff was pushed out of the presidency in an impeachment trial this August and replaced by a center-right leader, Michel Temer.

Story continues

Lula ridiculed the youthful corruption task force as "boy prosecutors" and said his enemies "persecuted the PT to stop me being a candidate in 2018."

Lula won plaudits in Brazil and around the world for lifting tens of millions of people from poverty with social programs while at the same time making the huge country relatively investor friendly.

However, that record is increasingly under strain as the scale of corruption during those years becomes clear and the economy, which was heavily dependent on high world commodity prices, founders.

Lula, wearing a brown suit with no tie, remains a powerful orator, alternating between angry shouts and emotion-filled near whispers. Defiant against what he considers to be a campaign to diminish his historic role and to destroy the PT, he is not shy about blowing his own trumpet.

"They say Lula compares himself to Jesus Christ," he said, referring to mocking accusations that he thinks too highly of himself.

"I don't compare myself to Jesus Christ," he said, before adding, "but I, too, was persecuted."