A 28-year-old Michigan man was arrested during a screening at the Capitol Visitor Center just after noon on Election Day for carrying a flare gun, torch lighter and bottles of fuel, police said.

Capitol Police later identified him as Austin M. Olson, of Westland, Mich., and said he is facing charges of possession of a prohibited weapon, unlawful activities and disorderly conduct.

“If our officers did not stop this man, yesterday would have been a very different story than this one,” Capitol Police Chief J. Thomas Manger said in a statement Wednesday. “All of our employees continue to work, together, around the clock during this heightened security environment.”

Police shut down the Capitol Visitor Center on Tuesday after detaining Olson, who had traveled by car to the Washington area on Nov. 4, according to Capitol Police.

At a press briefing after the arrest on Tuesday, Manger said the suspect entered the Capitol Visitor Center and placed a backpack and jacket on the conveyor belt. Officers saw something resembling a gun in his bag and smelled gasoline on his clothing and backpack, Manger said. 

Officers found a manifesto and a letter to Congress, which “focused on the man’s opinions on the war in the Middle East,” according to Capitol Police. They also found two bottles of fuel in his possession, police said. 

As of Tuesday afternoon, Manger said officers were still working to determine his intent. He said the man’s car was located several blocks from the Capitol.

“He had some articles in his backpack that he may have wanted to set on fire,” Manger said. “It did not appear that he had doused all of his clothing. There was some of his clothing that smelled like gasoline, but not all of it. So it’s really unknown at this point what his intention was.”

The visitor center was closed for the rest of the day as Capitol Police investigated.

The Capitol Visitor Center, the Library of Congress and the Botanic Garden were all open Tuesday despite heightened security throughout the city. The Library of Congress and Botanic Garden remained open to visitors.

Capitol Police put up bike rack barricades ahead of Election Day, as well as fencing on the west side of the campus around the area where the Inauguration Day stage will be located. Some businesses around the city boarded up their windows, and federal and local officials in the District of Columbia were bracing for potential unrest in the days and weeks to come.

“Beginning with early voting last week and through Election Day tomorrow and up until the inauguration, our team has one focus, and that is how to keep Washington, D.C., safe and secure for residents and visitors throughout election week and beyond,” D.C. Mayor Muriel Bowser said at a press briefing on security from Metropolitan Police headquarters Monday afternoon.

Metropolitan Police Department Chief Pamela Smith said the department would be working with Capitol Police and other law enforcement to ensure a safe post-election period.

“We are in close contact with the U.S. Capitol Police, as with our other federal partners, on a regular basis, a daily basis,” Smith said.