Chief Covelli said that Mr. Crimo had planned the shooting for several weeks, but authorities had not yet determined his motive. “We have no information at this time to suggest it was racially motivated, motivated by religion or any other protected status,” the chief said, adding that there was no indication that anyone else was involved.
Police have had at least two encounters with the suspect in the past.
People had contacted police twice in recent years with their concerns about Mr Crimo, Chief Covelli said.
April 2019: Someone contacted police after learning that Mr Crimo had recently attempted suicide. Chief Covelli said on Tuesday that police spoke to Mr Crimo and his parents about the case at the time, but declined to comment further as the case was being handled by mental health professionals.
September 2019: A member of the family of Mr. Crimo told police he had knives and would “kill everyone,” Chief Covelli said. Officers who went to the family home removed 16 knives, a dagger and a sword, but the chief said they had found no probable reason to make an arrest.
The shooter used a disguise to get away.
Authorities said the gunman was wearing women’s clothing to disguise his identity. He climbed a fire escape to access the roof where he carried out his attack, and after the shooting he climbed back down and left the scene on foot, amid fleeing parade-goers.
The police said that Mr. Crimo walked to his mother’s house in Highland Park and borrowed her car. He then drove to the Madison area of Wisconsin before returning to Illinois, Chief Covelli said. He was arrested after police in a nearby town spotted the car and tried to pull it over for a traffic stop.
The attack was one of many shootings in recent days.
The Highland Park mass shooting was the fourth in Illinois since Friday to hit at least four people, according to the Gun Violence Archive. The state has some of the strictest gun safety laws in the nation — including universal background checks, red flag warnings, and safe storage requirements — but is surrounded by states like Indiana that have far fewer restrictions on gun purchase and possession.
Ten hours before the shooting, around midnight, five people were shot at a residential complex in the Greater Grand Crossing neighborhood on Chicago’s south side. Two people were killed and seven injured in two separate shootings in Chicago on Friday, according to the Gun Violence Archive.
Also on Monday, the group reported shootings with four or more injured in Boston, Sacramento, Kansas City, Mo., and Richmond, Va.
In the hours following the parade attack in Illinois, bursts of gunfire killed or injured several people in Kenosha, Wis., and Gary, Ind., both within 60 miles of Highland Park.