The author of the massacre of July 4 in Chicago, accused of more than 100 charges

• 4th of July shooting Highland Park killer dressed as a woman to go unnoticed

• Chicago 4th of July Killer Nearly Opened Fire on Another Parade While Running From Police

US authorities charged the 21-year-old accused of carrying out a deadly mass shooting at a July 4 parade near

on Wednesday with 117 counts of murder and more, according to an official statement.

Robert Crimo,

a young man with a history of mental illness, opened fire at an

parade in a busy Chicago suburb, killing seven people and injuring dozens more.

Crimo, who was disguised as a woman during the shooting, was arrested several hours later.

He later confessed to the crime and said he was planning another attack.

Crimo was charged Wednesday with

as well as multiple counts of attempted murder and aggravated assault, according to a statement from prosecutors.

"Our investigation continues, and our victim specialists are working flat out to support everyone affected by this crime,"

said in a statement.

Crimo is expected to appear in court next week for his arraignment and charges will be officially read to him.

Robert Crimo.AP

The July 4 shooting was the last recorded large-scale gun massacre in the

where nearly 40,000 gun deaths occur each year, according to the

The event further ignited a tense national debate over gun control and raised questions about how someone with a history of mental health problems and threatening behavior would be allowed to legally purchase a gun.

Conforms to The Trust Project criteria

Know more

• Justice

• USA

• shootings

• Violence

• events