Police are preparing for total chaos at a Donald Trump rally that apparently gave out way too many free tickets

Republican presidential front-runner Donald Trump's campaign released 20,000 tickets for his Thursday rally in Burlington, Vermont, according to local police.

One problem: the venue seats just 1,400.

Burlington Police Department Deputy Chief Bruce Bovat told Business Insider he's aware of 18,000 people who have said they would attend the event. People have lined up outside of the Flynn Center, where the rally is being held, more than five hours in advance, CNN reported.

Bovat said thousands of potentially charged supporters and protesters would be turned away from Thursday's event, and he acknowledged that it could cause a chaotic mess outside the venue, which his department would have to manage.

"It's politics, there's a charged energy," he said. "We understand emotions fly high with this charged energy."

Bovat added that Trump's campaign did not communicate with city or police officials about releasing 20,000 free tickets to the event. He said, had Trump's campaign reached out to them, officials would've "strongly encouraged" the Trump campaign to release a "much, much lower number" of tickets.

"That seems to be the bone of contention for right now," he said. "No, there was no conference in which we had any input in that."

Trump's rallies have been the site of numerous small clashes between his supporters and those who protest the real-estate mogul's provocative campaign. Bovat said there would be a large police presence, including the Vermont State Police, local sheriff's deputies, and his own department. He also said there would be penned-off areas outside the event where people can voice their opinions.

Burlington Police Chief Brandon del Pozo told the Burlington Free Press that if a rock group sold that many tickets to a concert at the venue, the city would've canceled the event. But because it's a major presidential candidate coming to town, they are letting it go on.

"A lot of people with a lot of energy in a small venue, it only takes a spark," he said. "So we need to put out that spark as quick as we see it. In our world and in the world of public safety, you always plan for the worst and hope for the best. We're confident it's going to be good but we are prepared and we're not ignorant to the fact there could be some strong emotions and some things could flare up."

For his part, Trump simply encouraged his supporters to arrive early: