Pope Leo XIV has voted by mail in the US midterm elections, the Vatican said Friday, The Guardian and CBC News report. The Guardian says he is the first sitting pope known to have cast a ballot in any political election. CBC News says he is the first pope to vote in a US general election.

The Vatican said Leo "has exercised his right to vote as a United States citizen, whenever he was eligible to do so," the outlets report. "The Holy Father expresses his belief in the right and the duty of citizens to participate in democratic processes," the statement added.

Leo, who was known as Robert Prevost before he became pope, is registered at an address in New Lenox, Illinois, and asked for a mail-in ballot on October 3, the outlets report. That was 10 days before surgery to remove a cancerous tumor from his right lung. He left the hospital on October 17. CBC News says it is unclear how Leo returned the ballot.

The US Conference of Catholic Bishops praised the vote. "In voting, our Holy Father sets the example that encourages each citizen to exercise their civic responsibility," spokesperson Chieko Noguchi said, CBC News reports. Illinois records show Prevost asked for Democratic primary ballots twice and Republican primary ballots three times since 2000, the outlet reports.

Leo, the first American pope, has clashed with President Donald Trump over immigration and the US-Israeli war on Iran, The Guardian and CBC News report. The midterm elections are on November 3.

What we know: The Vatican says Leo voted by mail as a US citizen in the midterms.
What we don't: How he returned the ballot.