A man accused of opening fire on a Fourth of July parade near Chicago has been charged with seven counts of murder, officials say.
The 21-year-old would be punished "for the killing spree he has unleashed against our community", Lake County State Attorney Eric Rinehart said.
The attack in Highland Park left seven dead and more than 30 others injured.
Mr Rinehart added that dozens more charges would be filed before the investigation was over.
"These are just the first of many charges that will be filed," he said to cheers and applause from the crowd gathered for the news conference on Tuesday. "I want to emphasise that. There will be more charges."
If convicted, the seven murder counts alone would carry a mandatory sentence of life in prison without parole, Mr Rinehart said.
The suspect, Robert Crimo, is accused of firing 70 bullets from a high-powered rifle down on to the crowd and disguising himself as a woman so he could escape alongside fleeing victims.
After an eight-hour manhunt on Monday, police arrested the gunman and he was discovered with a second rifle similar to the one used in the attack.
Three other firearms were also found at his home. Police said the suspect had two prior contacts with law enforcement but was still able to purchase five guns in the past year.
Illinois state police said that the suspect's father sponsored his application for a firearm licence in December 2019, when he was just 19. But his uncle denied this in a statement to the Chicago Sun.
The parents requested privacy and expressed solidarity with the victims through a lawyer's statement.
"We are all mothers and fathers, sisters and brothers, and this is a terrible tragedy for many families, the victims, the parade-goers, the community, and our own," it said.
In April 2019, police were called to the suspect's home one week after he reportedly attempted to take his own life. And in September 2019, police were called by a family member who said he had made violent threats to "kill everyone".
Police responded and seized 16 knives, a dagger and a sword from his home. He was not arrested and no further action was taken.
Officials on Tuesday called for an education campaign to raise awareness of the state's red flag laws, which allow a judge to order that a person deemed dangerous have their weapons seized and be barred from buying more guns.
The suspect is expected to appear in court on Wednesday.
Six of the victims have been named so far. They include:
- Irina McCarthy, 35, and Kevin McCarthy, 37, died while protecting their two-year old son, who was uninjured
- Nicolas Toledo, 78, was visiting family when the Mexican father of eight was shot in his wheelchair
- Jacquelyn Sundheim, 63, worked at a local synagogue in Highland Park, which has a large Jewish population
- Stephen Straus, 88, was a financial advisor and father of two. His niece called him "an honourable man" who "worked his whole life"
- Katherine Goldstein, 64, had taken her daughter to Highland Park so she could reunite with school friends, the New York Times reported.
Many questions remain
By Nomia Iqbal in Highland Park, Illinois
People are in a state of shock here. Some who attended the parade have returned to pick up their belongings.
A few stand in silence as they survey the remnants and try to remember where they were sat or standing when the horror unfolded.
One woman who managed to escape said she is getting help from community counsellors to process what has happened.
The man accused of bringing terror to this town has now been charged with seven counts of murder - and there could be more to come.
Applause and cheers rang out as the state attorney read out the charges at a news conference.
But questions remain. It has been revealed that several years ago the suspect threatened to kill people and had a knife collection seized by police.
People here now want to know why he was able to legally purchase several firearms last year.