ROCKFORD, Ill. (AP) — A judge on Monday ordered a psychiatric evaluation for a northern Illinois man charged with killing four people and injuring seven others by stabbing, beating and driving over them.

Winnebago County Judge Debra Schafer ordered the evaluation for Christian Soto when the 22-year-old man appeared in court by video link for a scheduled arraignment on charges of first-degree murder.

Soto’s arraignment now is scheduled for May 17.

Assistant State’s Attorney Ken LaRue said the case would go before a grand jury on Friday.

Soto’s attorney, Glenn Jazwiec, said he had no comment on the judge’s order.

Authorities have said Soto was behind a series of frenzied attacks on March 27 at multiple addresses in a Rockford neighborhood, but they haven’t determined a motive.

The Winnebago County coroner has identified those killed as 63-year-old Romona Schupbach; 23-year-old Jacob Schupbach; 49-year-old Jay Larson; and 15-year-old Jenna Newcomb.