By Reg Chapman

ST. PAUL, Minn. (WCCO) — On Saturday in St. Paul, a peaceful demonstration at the Governor’s Residence turned into a confrontation when members of the group shut down both directions of Interstate 94 near Lexington Avenue.

WCCO’s cameras captured people throwing large rocks and other items at officers.

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Law enforcement did not expect to be assaulted when they agreed to escort protesters upset about the shooting death of Philando Castile at the hands of St Anthony police.

“The injuries that they had ranged from a separated shoulder to cuts and bruises,” said St. Paul Police Chief Todd Axtell.

A University of Minnesota officer received a serious spinal compression injury. The other 20 injured were taken to the hospital, treated and released.

“Even the officers that ended up going to the hospital several hours later stayed in their spot the entire time. Nobody tapped out,” said Axtell.

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St. Paul Police Chief Todd Axtell says it was a tense night for all involved — especially the families of officers who stood toe to toe with concrete throwing protesters. Axtell says he knows how they feel.

“Sitting in that command post, running that detail that night and knowing that my son was on that freeway was pretty chilling,” he said.

Axtell says officers know it was just a handful of people that decided to assault them and their actions do not represent the entire community.

“We have true professionals on this department. They did very good work protecting protesters and citizens and their fellow officers alike,” said David Titus, president of the St. Paul Police Federation.

Titus says officers will continue to serve and protect and will not let this incident destroy the sound relation police have with communities of color.

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“We have a strong history of promoting First Amendment rights and allowing peaceful passage throughout our city,” said Titus. “It’s worked for us in the past, we find it to be a very good recipe.”

Reg Chapman