Highland Park (Illinois): Highland Park's police chief said the 22-year-old man identified as a person of interest in the shooting that killed at least six people, wounded at least 30 and sent hundreds of people fleeing from an Independence Day parade in suburban Chicago on Monday has been taken into custody.

Police earlier said Robert E Crimo III should be considered armed and dangerous and was pulled over by police on Monday evening after a brief pursuit.

A gunman on a rooftop opened fire on an Independence Day parade in suburban Chicago on Monday, killing at least six people, wounding at least 30 and sending hundreds of marchers, parents with strollers and children on bicycles fleeing in terror, police said. The suspect remained on the loose hours later as authorities scoured the area and police surrounded a home listed as his possible address.

Highland Park Police Chief Lou Jogmen had said that police had identified 22-year-old Robert E Crimo III as a person of interest and cautioned he should be considered armed and dangerous. Police declined to answer questions about how they identified Crimo. Authorities had described his car as a silver Honda Fit with an Illinois license plate DM 80653.

The July 4 shooting was just the latest to shatter the rituals of American life. Schools, churches, grocery stores and now community parades have all become killing grounds in recent months. This time, the bloodshed came as the nation tried to find cause to celebrate its founding and the bonds that still hold it together.

"It is devastating that a celebration of America was ripped apart by our uniquely American plague, Illinois Governor J B Pritzker said at a news conference.

I'm furious because it does not have to be this way... while we celebrate the Fourth of July just once a year, mass shootings have become a weekly yes, weekly American tradition."

The shooting occurred at a spot on the parade route where many residents had staked out prime viewing points early in the day for the annual celebration. Dozens of fired bullets sent hundreds of parade-goers some visibly bloodied fleeing. They left a trail of abandoned items that showed everyday life suddenly, violently disrupted: A half-eaten bag of potato chips; a box of chocolate cookies spilled onto the grass; a child's Chicago Cubs cap.

There's no safe place, said Highland Park resident Barbara Harte, 73, who had stayed away from the parade fearing a mass shooting, but later ventured from her home.

Lake County Major Crime Task Force spokesman Christopher Covelli said at a news conference several of the deceased victims died at the scene and one was taken to a hospital and died there. Police have not released details about the victims or wounded.

Lake County Coroner Jennifer Banek said the five people killed at the parade were adults, but didn't have information on the sixth victim who was taken to a hospital and died there. One of those killed was a Mexican national, Roberto Velasco, Mexico's director for North American affairs, said on Twitter Monday. He said two other Mexicans were wounded.

NorthShore University Health Center received 26 patients after the attack. All but one had gunshot wounds, said Dr Brigham Temple, medical director of emergency preparedness. Their ages ranged from 8 to 85, and Temple estimated that four or five patients were children.

Temple said 19 of them were treated and discharged. Others were transferred to other hospitals, while two patients, in stable condition, remained at the Highland Park hospital.

The shooter opened fire around 10.15 am, when the parade was about three-quarters through, authorities said.

Highland Park Police Commander Chris O'Neill, the incident commander on scene, said the gunman apparently used a high-powered rifle to fire from a spot atop a commercial building where he was very difficult to see. He said the rifle was recovered at the scene. Police also found a ladder attached to the building.

Very random, very intentional and a very sad day, Covelli said.

President Joe Biden on Monday said he and first lady Jill Biden were shocked by the senseless gun violence that has yet again brought grief to an American community on this Independence Day. He said he had surged Federal law enforcement to assist in the urgent search for the shooter, who remains at large at this time.

Biden signed the widest-ranging gun violence bill passed by Congress in decades, a compromise that showed at once both progress on a long-intractable issue and the deep-seated partisan divide that persists.

Police believe there was only one shooter.

Several nearby cities cancelled events including parades and fireworks, some of them noting that the Highland Park shooter was still at large. Evanston, Deerfield, Skokie, Waukegan and Glencoe cancelled events. The Chicago White Sox also announced on Twitter that a planned post-game fireworks show is cancelled due to the shooting.

More than 100 law enforcement officers were called to the parade scene or dispatched to find the suspected shooter.

More than a dozen police officers on Monday evening surrounded a home listed as an address for Crimo in Highland Park. Some officers held rifles as they fixed their eyes on the home. A large armoured truck, marked Police Rescue Vehicle, occupied the middle of the road near the residence. Police blockaded roads leading to the home in a tree-lined neighbourhood near a golf course, allowing only select law enforcement cars through a tight outer perimeter.