June 3 (UPI) -- Minnesota authorities on Wednesday escalated the murder charge against former Minneapolis police officer Derek Chauvin and levied charges against the other three officers involved in the arrest and death of George Floyd.
Minnesota Attorney General Keith Ellison announced the new charges in an afternoon news conference.
"Today, I filed an amended complaint that charges former Minneapolis police officer Derek Chauvin with murder in the second-degree in the death of George Floyd," he said.
"Second, today, arrest warrants were issued for former Minneapolis police officers J. [Alexander] Kueng, Thomas Lane and Tou Thao," charging them with aiding and abetting murder in the second-degree, Ellison added.
All three of the officers facing fresh charges Wednesday were arrested and booked by the Hennepin County Sheriff's Office. Chauvin has been in detention at Oak Park Heights state prison since Sunday.
Sen. Amy Klobuchar, D-Minn., reported the charges on Twitter.
"Minnesota Attorney General Keith Ellison is increasing charges against Derek Chauvin to 2nd degree in George Floyd's murder and also charging other 3 officers. This is another important step for justice," she tweeted.
Ellison asked for the public's patience during the ongoing investigation.
"As we develop a case for prosecution, we also will not be able to say much about it," he said, adding that investigators are working "as quickly as we can."
The officers arrested Floyd outside a Cup Foods store on May 25 after a clerk reported that he used a counterfeit $20 bill.
Video of the police interaction showed Chauvin kneeling on Floyd's neck for more than 8 minutes as the latter was on the ground, calling out that he couldn't breathe.
The Minneapolis Police Department fired the four officers one day after Floyd's death, and the Hennepin County Attorney's Office initially charged Chauvin with third-degree murder.
Minnesota Gov. Tim Walz on Tuesday asked Ellison to take over the prosecution of the officers, leading to the new charges.
"This is a bittersweet moment for the family of George Floyd," said Benjamin Crump, an attorney representing the Floyd family.
"We are deeply gratified that Attorney General Keith Ellison took decisive action in this case, arresting and charging all the officers involved in George Floyd's death and upgrading the charge against Derek Chauvin to felony second-degree murder," the statement continued.
In Minnesota, first- and second-degree murder mean prosecutors must be able to prove that Chauvin intended to kill Floyd. Under third-degree murder, the defendant committed the crime against a person they believed to be "eminently dangerous to others and evincing a depraved mind, without regard for human life."
Floyd's death prompted protests across the globe calling for police reforms and an end to systemic racism.