Hennepin County Attorney Mike Freeman announced this afternoon Derek Chauvin, the Minneapolis police officer seen kneeling on 46-year-old George Floyd’s neck until he could not breathe, has been charged with third-degree murder and manslaughter.

Freeman said the evidence against Chauvin includes footage from a bystander’s cell phone, body camera footage as well as statements from witnesses and a preliminary report from the medical examiner.

“We felt in our professional judgment that it was time to charge and we have so done it,” Freeman said.

He later added he expected additional charges to be brought against the other officers involved in the incident, but did not go into detail.

Chauvin’s arrest follows three days of protests across Minneapolis that led to looting, violence and a police precinct being torched.

Minnesota Governor Tim Walz today promised swift justice in Floyd’s death, but also pleaded with protestors who have set fire to Minneapolis to stop, so the city could restore justice and order.

“I won’t patronize you as a white man about living those experiences but I am asking you to help us,” Walz said. “Help us use humane ways to get the streets to a place where we can restore the justice so that those who are expressing rage and anger and demanding justice are heard, not those who throw fire bombs into businesses.”

Walz added that that the looting and violence was counterproductive to the ultimate goal of seeking justice for Floyd and that underlying issues involved in Floyd’s death could not be addressed until there was calm.

“We can’t have it because we can’t function as a society and I refuse to have it take away from the attention of the state,” he said.

Walz also referenced Philando Castile and other black people who have died in Minnesota at the hands of police.

“Their voices went unheard, and now generations of pain is manifesting itself in front of the world,” Walz said. “And the world is watching.”

About a half hour ahead of Waltz’s press conference, President Trump tweeted, “The National Guard has arrived on the scene. They are in Minneapolis and fully prepared. George Floyd will not have died in vain. Respect his memory!!!”

Floyd died in police custody Monday night.

He had been arrested after an employee at a grocery store called police to accuse Floyd of trying to pass a counterfeit $20 bill.

Floyd, who is black, was then handcuffed by Chauvin, who is white, and pushed to the ground. A cell phone video shows Floyd’s head is turned to the side and he does not appear to be resisting. Chauvin has his knee pressed to the back of Floyd’s neck for several minutes as Floyd is seen gasping for air and begging Chauvin to stop. He does not. Bystanders are also heard shouting at Chauvin to take his knee off Floyd’s neck.

Tou Thao, the second officer seen in the video, does nothing as Floyd struggles for several minutes before going limp.

Together, Chauvin and Thao have had more than a dozen conduct complaints against them in the past, but have not been formally reprimanded.

The two other officers were at the scene were Thomas Lane and Alexander Kueng.

All four have been fired.

The video footage of Floyd’s death ignited simmering racial tensions in the city and has shined a light on the use of force by police officers against black residents.