Leftist supporters of former president Luiz Inácio Lula da Silva have surrounded Sao Paulo, Brazil’s Metalworkers’ Union headquarters, where Lula has remained in hiding after the nation’s top court decreed he could begin serving a 12-year prison sentence on corruption charges immediately.

Lula, the head of the nation’s socialist Workers’ Party (PT), is running for president in Brazil’s October elections and remains the frontrunner by a wide margin in most recent polls. Despite being convicted of corruption and money laundering, and losing an appeal on the merits, his attorneys petitioned the Supreme Federal Tribunal (STF) for a habeas corpus writ that would keep him out of jail until he had exhausted his final appeal on the case. The STF ruled early Thursday morning, in an extensive 11-hour ruling, against the petition, meaning Lula would have to begin his prison sentence as soon as the judge presiding over the original case, Judge Sergio Moro, chose to call him in. Lula has remained in the Metalworkers’ Union building since then, receiving a visit from fellow disgraced ex-president Dilma Rousseff overnight.

Moro announced on Thursday that he would give Lula until Friday 5 p.m. local time to turn himself in willingly to police in Curitiba. If not, Moro would issue a warrant for his arrest. Should he turn himself in willingly, Lula would receive, among other perks, a more secure private prison cell to keep him from common criminals.

Lula told the city newspaper Folha de Sao Paulo on Friday that he did not plan to turn himself into authorities in Curitiba, which will result in the court charging him for resisting arrest and may hurt his chances to overturn the case on his final appeal. As an official warrant will only exist upon Moro writing it when Lula fails to meet the voluntary deadline, some experts believe that Lula’s peaceful arrest would not constitute any violations even if refusing to hand himself him. The greater issue is the potential for violence in the event that police send officers to arrest Lula.

Several of his closest advisers appear to have confirmed that Lula will not turn himself in. Former presidential special adviser Gilberto Carvalho, who remains with Lula at the Metalworkers’ Union headquarters, told Estadao that the PT’s plan is to flood the outside of the building with supporters and make it impossible for police to enter the building and arrest Lula.

“[The plan] is to resist, of course,” Carvalho said. “I want the people to make a human chain to stop the arrest, that’s all we have to do.”

Estadao notes that Carvalho replied to concerns that such an event would worsen the situation with the question, “worsen what?”

Former PT head Rui Falcao similarly confirmed to journalists that Lula would not travel to Curitiba and hand himself in.

The PT has confirmed that Lula plans to address those congregated around the building at 4 p.m. local time, an hour before law enforcement has ordered him to turn himself in.

Legal experts suggest that police may wait until dawn for an early-morning raid on the building to arrest him. Police officials have denied having a plan at the moment to raid the building, however, citing the high potential for violence.

In the meantime, leftists have surrounded the building where Lula is staying, most dressed in the socialists’ red color and bringing an assortment of flags for their special issues. O Globo reports that those congregating outside have created a tailgate atmosphere, setting up grills for traditional churrasco meats and drinking beer while they wait for the inevitable confrontation between the convict and presidential hopeful and the police. The newspaper estimates that around 500 people have surrounded the building.

The leftists have already engaged in violent activity, in particular turning against the journalists covering the event. The magazine Veja reports that protesters have attacked reporters and photographers, irritated that their coverage may reveal that the number of people surrounding the building has dwindled. Journalists, meanwhile, have complained of a lack of police protection in the area.

Lula was arrested as part of a larger police investigation known as “Operation Car Wash,” which revealed a mammoth corruption scheme built during Lula’s tenure in which the state oil company Petrobras would overpay willing contractors for public projects. The contractors would then kick back the excess taxpayers’ dollars to politicians to ensure that they would continue to receive the contracts. Lula was convicted of using bribery money from this scheme to purchase a luxury beachfront property.

If he is imprisoned and kept off the presidential ballot, conservative lawmaker Jair Bolsonaro is expected to be the frontrunner in October’s presidential race.

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