A Supreme Court justice ruled Wednesday President Jair Bolsonaro should be investigated for unproven claims Brazil’s voting system is riddled with fraud, adding the far-right leader to an ongoing probe on the spread of fake news by his government.

The ruling by Justice Alexandre de Moraes came after Bolsonaro stepped up his longtime attacks on Brazil’s electronic voting system, claiming — without evidence — that it is fraud-plagued and insisting there will be no elections next year as scheduled if it is not overhauled.

The Superior Electoral Court had asked the Supreme Court to issue the ruling, after itself putting the president under investigation for his campaign against Brazil’s voting system.

The Supreme Court agreed, finding Bolsonaro should face investigation for slander and inciting criminal acts for his undocumented claims of massive vote fraud.

The electoral court’s own probe will investigate the president for abuse of office, improper use of official communication channels, corruption, fraud and other potential crimes.

Bolsonaro has long criticized electronic voting, introduced in Brazil in 1996.

He has stepped up his attacks in the build-up to the October 2022 elections, insisting on “printable and auditable” paper ballots as a backstop to the electronic system.

Opinion polls place the 66-year-old leader well behind leftist ex-president Luiz Inacio Lula da Silva in the presidential race.

Bolsonaro’s popularity numbers have been sliding, and he is under fire on various fronts, including a Senate investigation into his government’s widely criticized handling of Covid-19.

There are fears Bolsonaro could try to use fraud claims to undermine next year’s election if he loses, following in the footsteps of former US president Donald Trump, with whom he is often compared.

‘Brazil is under attack’

Bolsonaro lashed out at the electoral court’s investigation Tuesday.

“I refuse to be intimidated,” he fired back.

“I’m going to continue exercising my right to freedom of expression, to criticize, to listen to and above all answer to the will of the people,” he told supporters outside the presidential palace.

“I swore to give my life for the nation in case of foreign or domestic attack. Brazil is under internal attack.”

Voters in Brazil cast their ballots electronically at polling stations.

Bolsonaro has for years been arguing for a paper printout to be made of each vote cast, saying the absence of a paper trail makes cheating easier.

He threw fuel on the fire surrounding his claims with a Facebook live address last Thursday in which he spent the better part of two hours insisting the 2014 and 2018 elections were fraudulent.

He says his own victory in 2018 should have come in the first round, rather than the runoff, though he has never presented evidence to back up the claim.

On Sunday, thousands of Brazilians took to the streets in several cities to support Bolsonaro’s campaign against electronic voting.

The president himself did not take part.