Minnesota Attorney General Keith Ellison will charge the three other ex-police officers involved in George Floyd’s death and upgrade the charges against Derek Chauvin — the officer who knelt on Floyd’s neck — to second-degree murder, the Star Tribune reports.

All four officers — Chauvin, Tou Thao, J. Alexander Kueng and Thomas Lane — were fired the day after Floyd’s death, but up until today only Chauvin had been arrested and charged. The other three will now be charged with aiding and abetting second-degree murder.

Protesters and activists have long been calling for Thao, Kueng and Lane to face criminal charges alongside Chauvin. In the video of Floyd’s death, Kueng can be seen pinning Floyd; Thao can be seen watching Chauvin hold his knee to Floyd’s neck while Floyd repeatedly states he can’t breathe; and Lane can be heard expressing some concern and asking whether Floyd should be rolled over onto his side, which Chauvin rejects.

The charges against the three other officers come one day after Minnesota Governor Tim Walz asked Ellison to take over the case from the Hennepin County Attorney’s Office. They also follow the results of an independent autopsy, requested by lawyers for Floyd’s family, which found that Floyd died not only because Chauvin kept his knee on Floyd’s neck, but because the other officers helped hold Floyd down. For instance, another officer’s knee, pressed against Floyd’s back, reportedly compressed his lungs and made it harder for him to breathe. Meanwhile, an official autopsy from the Hennepin County Medical Examiner ruled Floyd’s death a homicide and stated that he “experienced a cardiopulmonary arrest while being restrained by law enforcement officer(s).”

As for the upgraded charges for Chauvin to second-degree murder, activists and legal experts had been calling for such a move because they believed that third-degree murder would be easy for Chauvin to beat. In a statement released last week, ACLU Minnesota said: “Minnesota courts have repeatedly ruled that to support a charge of Third Degree Murder, the offender’s actions need to be ‘eminently dangerous to more than one person.’ … Officer Chauvin’s actions were directed solely toward George Floyd and were not ’eminently dangerous’ to anyone other than George Floyd, although Chauvin and the other officers may well have been aware that their actions would ultimately spark the public outrage that has ravaged the Twin Cities ever since. The charge for Third Degree Murder therefore potentially will not stick.”

Benjamin Crump, a lawyer representing Floyd’s family, reacted to the new charges on Twitter, saying: “This is a bittersweet moment. We are deeply gratified that @AGEllison took decisive action, arresting and charging ALL the officers involved in #GeorgeFloyd’s death and upgrading the charge against Derek Chauvin to felony second-degree murder.”

Chauvin has retained defense attorney Tom Kelly, who successfully defended Jeronimo Yanez, the police officer who was charged and acquitted of manslaughter in the 2016 death of Philando Castile. Kelly did not immediately return Rolling Stone‘s request for comment.