Brazilian President Jair Bolsonaro successfully underwent a fourth abdominal surgery for a year-old stab wound on Sunday. Bolsonaro was stable after the five-hour surgery, according to a statement from the presidential palace. Adélio Bispo de Oliveira, a mentally ill man, stabbed Bolsonaro last September at a political rally in Juiz de Fora. He was later acquitted of any crime after being diagnosed with mental illness. He is currently detained in a mental health clinic indefinitely.

The 64-year-old president tweeted a message of hope before he was admitted to the hospital on Saturday: “I remain confident for the next surgery,” he wrote on Twitter. “May God bless us. Good night.” Hamilton Mourao, Brazil’s vice president, will serve as acting president through Thursday as Bolsonaro recovers, his spokesman said Sunday.