On Monday, Bolivia former President Evo Morales left for Mexico, where he accepted political asylum one day after resigning following what he has described as a “coup.”

The longest-serving president of the South American country stepped down on Sunday after weeks of protests about election fraud following the October 20 presidential election and the release of a report from the Organization of American States (OAS) over the weekend that found “serious irregularities” around the vote count.

Morales said he was urged by military to step down and that he and some of his supporters have experienced violence. As a result, the politician announced that he was accepting political asylum in Mexico in a Tweet late Monday.

“Sisters and brothers, I leave for Mexico, grateful for the detachment of the government of that brother town that gave us asylum to take care of our lives,” he said. “It hurts to leave the country for political reasons, but I will always be alert.”

Later, Mexican Foreign Minister Marcelo Ebrard confirmed Morales’ move by tweeting a photo of the former president on a plane holding the Mexican flag.

“His life and integrity are secure,” Ebrard wrote.

Mexico is one of multiple Latin American countries that have supported Morales. Cuban President Miguel Díaz-Canel and Venezuelan President Nicolás Maduro have also stated that the former president is the victim of a coup.

In the U.S., Democratic presidential candidate Bernie Sanders said he was “very concerned about what appears to be a coup in Bolivia, where the military, after weeks of political unrest, intervened to remove President Evo Morales.”

He continued: “The U.S. must call for an end to violence and support Bolivia’s democratic institutions.”

President Donald Trump, however, described it as a moment for celebration.

“The United States applauds the Bolivian people for demanding freedom and the Bolivian military for abiding by its oath to protect not just a single person, but Bolivia’s constitution,” Trump said in a statement, according to Bloomberg.

Following Morales, three officials next in the presidential line of succession resigned as well. Second vice president of Bolivia’s senate, Jeanine Añez, said she is up next to assume the presidency.