Attorney General Keith Ellison plans to elevate charges against the former Minneapolis police officer who knelt on George Floyd's neck while adding charges of aiding and abetting murder against the other three officers at the scene, according to multiple law enforcement sources familiar with the case.

Ellison is expected to provide an update this afternoon on the state's investigation into Floyd's death. According to sources, former officer Derek Chauvin, recorded on video kneeling on Floyd's neck as he begged for air on May 25, will now be charged with second-degree murder.

The other three officers at the scene — Tou Thao, J. Alexander Kueng and Thomas Lane — will also be charged with aiding and abetting second-degree murder, according to the sources, who spoke on conditions of anonymity. Chauvin was arrested last Friday and charged with third-degree murder and manslaughter.

Thao was recorded watching as Chauvin continued to press on Floyd's neck with his knee. Kueng was one of the first officers on the scene and helped pin Floyd down. Lane was detailed in earlier charges as pointing a gun at Floyd before handcuffing, and later asked whether officers should roll Floyd on his side as he was restrained.

The charges come just days after Gov. Tim Walz asked Ellison to take over the prosecution, which until Sunday had been led by the Hennepin County Attorney's Office.