BRASILIA, Aug 12 (Reuters) - Brazilian Supreme Court Justice Alexandre Moraes on Thursday opened a probe into right-wing President Jair Bolsonaro for posting documents to social media from a sealed police investigation into the hacking of a federal election court. The hack of the Superior Electoral Court occurred months before the 2018 election, with Bolsonaro posting the documents last week while persistently claiming that the election system is open to fraud. The president has not presented proof to back up those allegations. Moraes ruled that Bolsonaro"s posts must immediately be removed from social media and that the police officer leading the inquiry be removed. Bolsonaro responded in his weekly online live broadcast, saying that the classified investigation should be public. "The federal police investigation interests all of us, so it has to be public. If not, how long will it stay under seal?" Bolsonaro asked. He said that even if his posts were removed online, the documents had already been widely circulated. Judges on the electoral court had requested an inquiry be opened into the matter earlier in the week. Bolsonaro last week accused the court of hiding the attack and claimed hackers had gained access to the voting machines" source code, which could be used to tamper with the vote. The electoral court has said the 2018 hack had not affected that year"s elections, adding that police had not found risk of fraud in the voting system. Moraes had already approved an investigation into Bolsonaro"s unfounded accusations that the electronic voting system is open to fraud. Bolsonaro has said that investigation is unconstitutional, threatening to act outside the bounds of the constitution in response, without specifying how. read more Congress defeated Bolsonaro"s campaign earlier this week to adopt a paper record of each vote, in another blow to his weakened political position heading into the 2022 elections. read more