Former Brazilian President Luiz Inacio Lula da Silva surrendered to the police on Saturday, more than 24 hours after a court deadline to turn himself in ended, Reuters reported. Lula spent two nights at the metalworkers’ union headquarters in São Paulo, after the Supreme Court ruled on Thursday that he must start serving a 12-year prison sentence for corruption.

Lula was surrounded by hundreds of supporters as he was taken to Curitiba city to serve his sentence. Police officers had to use stun grenades, tear gas and rubber bullets to disperse the crowds.

The 72-year-old is considered one of Brazil’s most popular politicians, and had over 80% approval ratings when he left office in 2011, The Guardian reported. Silva has been leading opinion polls ahead of elections in the country in October.

“Do what you want, the powerful can kill one, two or 100 roses,” Lula had told his supporters in a speech earlier in the day. “But they’ll never manage to stop the arrival of spring.”

He has insisted he was innocent and called his bribery conviction a political crime. “I will comply with the order,” he said. “I’m not above the law. If I didn’t believe in the law, I wouldn’t have started a political party. I would have started a revolution.”