In what has become a typical Trump rally brouhaha, a protest against the presumptive Republican presidential nominee in Denver, Colorado grew violent, with pushing and shoving. At least three people were arrested.

As Donald Trump spoke at the Western Conservative Summit on Friday morning, hundreds demonstrators gathered outside the Colorado Convention Center and in Civic Center Park. About half an hour after the GOP candidate was scheduled to begin his remarks, pushing and shoving broke out between protesters.

Fight just broke out at the Denver Trump protest. pic.twitter.com/zt8cFzJarm — Jim Dalrymple II (@JimDalrympleII) July 1, 2016

Denver Police, expecting a large number of protesters and hoping to prevent violence, had a strong presence outside the convention center, KUSA reported.

Current police situation at the Trump protest in Denver. pic.twitter.com/3MV12pJopH — Jim Dalrymple II (@JimDalrympleII) July 1, 2016

“We have certainly taken into account that there have been issues at similar events in other cities, and we have incorporated that into our safety plan,” Denver Police Department spokesperson Doug Schepman told reporters on Thursday.

Heavy Denver Police presence outside the Trump rally- generally under control. pic.twitter.com/zPrcfaJ6pd — Trevor Hughes (@TrevorHughes) July 1, 2016

Three people were taken into custody during the protest, authorities said.

This is the protester who was taken into custody while holding a bundle of burning sage. She was just released pic.twitter.com/OOpOxLyKvq — Jim Dalrymple II (@JimDalrympleII) July 1, 2016

The Western Conservative Summit, an annual event hosted by the Centennial Institute, is a three day conference that bills itself as "the largest gathering of conservatives outside of Washington, DC."

A man in a EZLN t-shirt emblazoned with the logo of the communist Mexican rebels, hung Trump in effigy.

Trump protesters now in front of the CO Convention Ctr.#trump#westernconservativesummitpic.twitter.com/QjMesUO8YN — KOA NewsRadio (@KOANewsRadio) July 1, 2016

Trump effigy at the coven toon center #9newsmorningspic.twitter.com/Dvxat2gcfM — Matthew Bell (@TheVagus) July 1, 2016

Black Bloc protesters and members of Occupy Denver were also present.

Occupy Denver protesters have shown up outside the convention Ctr. #Trump#westernconservativevsummitpic.twitter.com/NcNojQhRnQ — KOA NewsRadio (@KOANewsRadio) July 1, 2016

In Civic Center Park, groups built a 9-foot high, 30-foot long wall out of 3-foot by 3-foot boxes to protest Trump’s visit. The structure is meant as a visible demonstration against the candidate’s proposal to build a wall along the US-Mexican border, organizers told KDVR. After the wall is constructed, artists will paint the boxes, which will then be filled with donated goods and given to charities that help immigrants.

“Instead of building walls of separation and hatred and supremacy, we are actually showing that we as a community can come together and build something good for the community,” Ian Silverii, executive director of ProgressNow Colorado, told the Colorado Springs Gazette.

Putting out the welcome wall for Trump in Civic Center Park pic.twitter.com/Jj2f86s3wZ — Paul Karolyi (@PaulKarolyi) July 1, 2016

“We’re showing the world that Colorado doesn’t break out into the violence and chaos that seems to happen whenever Trump shows up. We’re bringing people together to do something good instead.”

So much for that idea...