US authorities indicted the 21-year-old man accused of carrying out a deadly mass shooting at a July 4 parade near Chicago on 117 counts of murder and other charges, according to an official statement.
Robert Crimo, a young man with a history of mental illness, opened fire on an Independence Day parade in an affluent Chicago suburb, killing seven people and injuring dozens more.
The attack was the latest in the wave of gun violence plaguing the United States.
Crimo, who was disguised in women's clothing during the shooting, was arrested several hours afterwards. He later confessed to the crime and said he was planning another attack.
Crimo was charged on Wednesday with 21 counts of first-degree murder, as well as multiple counts of attempted murder and aggravated battery, according to a statement from prosecutors.
"Our investigation continues, and our victim specialists are working around the clock to support all those affected by this crime," Lake County State's Attorney Eric Rinehart said in a statement.
Crimo is set to appear in court next week for his arraignment and have the charges officially read to him.
The July 4 shooting was the latest large-scale gun massacre in the United States, where about 40,000 deaths a year are caused by firearms, according to the Gun Violence Archive.
The shooting further ignited a tense national debate on gun control and raised questions about how a person with a history of mental health problems and threatening behavior was allowed to legally purchase firearms.
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