Donald Trump has taken to wearing a bulletproof vest on the campaign trail, according to a report published Sunday in New York Magazine.

The vest, two anonymous campaign sources told reporter Gabriel Sherman, was wearing on Trump. Sherman reported Trump’s vest “has added to his discomfort on the stump, leaving him sweaty and spent after events.”

The news comes after Trump rallies grew increasingly violent last month. At one campaign stop in Ohio, Secret Service agents swarmed the candidate as one protester tried to make his way onto the stage where Trump was speaking.