Lula sworn in as President of Brazil after defeating outgoing Jair Bolsonaro

The leftist, known as Lula, assumed office for the third time, marking a return to the job he held from 2003 to 2010.

It came after he defeated his predecessor Jair Bolsonaro in a bitter – and extremely close – presidential election in October, in a political comeback that has thrilled supporters and enraged opponents in the fiercely polarised nation.

In a break with tradition, Bolsonaro was absent from the inauguration, having reportedly flown to the US on Friday.

Security was stringent at Sunday’s ceremony, amid fears supporters of Bolsonaro would cause disruption.

Early on Sunday afternoon, people wearing the red of Lula‘s Workers’ Party flooded into Brasilia’s main esplanade to enjoy live music and await the start of official events.

They chanted Lula‘s name and sang the lyrics of a song that informs Bolsonaro it is time for him to leave.

Lula’s presidency is unlikely to be like his previous two mandates, coming after the tightest presidential race in more than three decades in Brazil and resistance to his taking office by some of his opponents, political analysts say.

The leftist defeated far-right Bolsonaro in the October 30 vote by less than 2 percentage points.

For months, Bolsonaro had sown doubts about the reliability of Brazil’s electronic vote and his loyal supporters were loath to accept the loss.

Many have since gathered outside military barracks, questioning results and pleading with the armed forces to prevent Lula from taking office.

Bolsanaro’s most die-hard backers resorted to what some authorities and incoming members of Lula’s administration labeled acts of “terrorism” – which have prompted growing security concerns about inauguration day events.

“In 2003, the ceremony was very beautiful. There wasn’t this bad, heavy climate,” said Carlos Melo, a political science professor at Insper University in Sao Paulo, referring to the year Lula first took office. “Today, it’s a climate of terror.”

With tensions running hot, a series of events has prompted fear that violence could erupt during Lula’s inauguration on Sunday.

On December 12, dozens of people tried to invade a federal police building in Brasilia, and burned cars and buses in other areas of the city.

Then on Christmas Eve, police arrested a 54-year-old man who admitted to making a bomb that was found on a fuel truck headed to Brasilia’s airport. He had been camped outside Brasilia’s army headquarters with hundreds of other Bolsonaro supporters since November 12.

He told police he was ready for war against communism, and planned the attack with people he had met at the protests, according to excerpts of his deposition released by local media.

The next day, police found explosive devices and several bulletproof vests in a forested area on the federal district’s outskirts.

Lula has made it his mission to heal divided Brazil. But he will have to do so while navigating more challenging economic conditions than he enjoyed in his first two terms, when the global commodities boom proved a windfall for Brazil.

The nation’s economy has since plunged into two deep recessions and ordinary Brazilians have suffered greatly.

Lula has said his priorities are fighting poverty, and investing in education and health. He has also said he will bring illegal deforestation of the Amazon to a halt.