SAO PAULO (Reuters) - The commander of Brazil’s army ratcheted up tension on the eve of a Supreme Court decision on whether former President Luiz Inacio Lula da Silva should be allowed to exhaust his appeals process before being sent to jail for a corruption conviction.

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General Eduardo Villas Boas wrote on his verified Twitter account on Tuesday evening that the army was “attentive to its institutional missions” and that the military, along with “all good citizens, repudiates impunity and respects the Constitution, social peace and democracy.”

The commander added that “in Brazil’s current situation, it is up to the institutions and citizens to ask who is really thinking of the well-being of our country and its future generations and who is only concerned about personal interests.”

Villas Boas did not elaborate. Calls to the army’s press office were not answered. Army representatives confirmed to Brazilian newspaper Folha de S.Paulo that the tweets were written by the general.

The comments came as thousands of Brazilians rallied in cities around Brazil to both support and decry Lula, who has said he wants to run for the presidency again in October. He leads polls by a wide margin, but may be barred from running after his bribery conviction was upheld on appeal.

The words of Villas Boas were splashed across the websites of Brazil’s major news outlets and drew support on Twitter from active army generals, but others bristled, warning of lessons learned from Brazil’s 1964-85 military dictatorship.

“In a democracy, a military commander does not send a message to any power of the Republic,” wrote federal lawmaker Chico Alencar on Twitter. “2018 is not 1964!”

Lula’s detractors say he was the ringleader of a sprawling political bribery scheme that saw billions of dollars in kickbacks paid to politicians by the executives they appointed at state-run companies in return for lucrative contracts.

Supporters of Lula, who faces six separate graft trials in addition to the one in which he was already convicted, say he was wrongly found guilty by a partial judge who wants to block him from regaining the presidency.

Lula was sentenced to more than 11 years in prison in his first trial. He has asked the top court to allow him to remain free until his appeals are exhausted, despite a law allowing judges to imprison those found guilty of a crime once the ruling is upheld on appeal. Lula’s conviction was upheld in January.

Lula denies any wrongdoing and has accused Brazil’s judiciary of convicting him with scant proof to halt his political comeback. He has vowed that he will run for the presidency, even from a jail cell.

Any politician with a conviction upheld on appeal is barred from running for office for eight years in Brazil. It falls to the country’s top electoral court to make a ruling on whether Lula can run only after he officially registers as a candidate.