Police arrested a man Monday after he walked onstage and interrupted GOP Rep. Chris Stewart of Utah at a debate with Democratic opponent Shireen Ghorbani.

Law enforcement arrested Corbin Cox McMillen and charged him with disorderly conduct and interrupting a political meeting, a Class B misdemeanor, for leaning into Stewart’s microphone during his closing statement and loudly stating a conspiracy theory about a connection between vaccines and autism, according to KUTV in Utah.

The interruption came at the end of the debate held at Dixie State University in Utah’s 2nd District.

“Vaccines cause autism,” said the man, who wore a loose white button-down tucked into khaki pants as he bent at the waist over Stewart’s podium. “Autism is caused by vaccines.”

Dixie State University police quickly rushed onstage and arrested McMillen as the debate moderator apologized to the flustered congressman.

“All right, I guess he got my closing statement, is that right?” Stewart joked.

During the debate, Stewart criticized Trump for imposing harsh tariffs on countries and organizations like China, Canada and the European Union as part of his escalating trade war with them, The Salt Lake Tribune reported. Some of the president’s tweets are “indefensible,” the congressman said.

But the economy is humming, he said, and Trump’s tax code overhaul deserves credit.

“Because of that tax reform we have the strongest economy we’ve had since I’ve been alive,” Stewart said.

Ghorbani shot back that the tax cuts benefit large corporations and the already wealthy.

The candidates touched on a number of environmental, economic and foreign policy-related topics.

Most experts do not expect the 2nd District, which encompasses the largest geographical swath of the four districts in Utah, to be competitive.

Stewart is seeking a fourth term there. He defeated his 2016 Democratic challenger by 28 points. President Donald Trump carried the district by 14 points over Hillary Clinton.

Inside Elections with Nathan L. Gonzales rates the race Solid Republican.