The mayor's eyes appeared red from tears as, just a few miles away, firefighters were still dousing flames from protests that turned violent overnight, demonstrations that erupted after Floyd's death in police custody on Monday.
"What we've seen over the last two days ... is the result of so much built-up anger and sadness," he told reporters. "Anger and sadness that has been ingrained in our black community, not just because of five minutes of horror, but 400 years.”
He added: “If you’re feeling that sadness and that anger, it’s not only understandable, it’s right.”
Full coverage of George Floyd's death and protests around the country
City Council Vice President Andrea Jenkins, a former performance artist, sang "Amazing Grace" before speaking to reporters.
She declared that racism is a "public health issue" no less serious than cancer.
"Until we name this virus, this disease that has has infected American for the past 400 years, we will never ever resolve this issue," she said. "If you don’t call cancer what it is, you can never cure that disease."
Before leaving the podium, she turned to her right, where police chief Medaria Arradondo was approaching, and declared: "We gotta make a change, bro."
Four of Arradondo's officers have been fired since Floyd died in police custody. Minneapolis police said in a statement early Tuesday that the officers were responding to a report of a forgery when Floyd "physically resisted" and that he died after "suffering medical distress."
Passers-by captured video of officer Derek Chauvin, who is white, putting his knee on the neck of Floyd, a black man, for several minutes as Floyd repeatedly said, "I can't breathe."
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Chief Arradondo said he understood the anger of protesters, but said he's duty-bound to restore order against looters and arsonists.
“I know that there is currently a deficit of hope in our city. And as I wear this uniform before you, I know this department has contributed to that deficit of hope," he said.
"But I will not allow (anyone) to continue to increase that deficit by re-traumatizing those folks in our community."
Mayor Frey and Council VP Jenkins also appealed to protesters and begged them not carry out the carnage that exploded Wednesday night into Thursday morning.
"You have every absolute right to be angry, to be upset, to express your anger," Jenkins said. "However, you have no right tp perpetrate violence and harm on the very communities that you say you are standing up for. We need peace and calm in our streets and I am begging you for that calm."