The suspect was arrested after the deadly gun attack at a US National Day parade near Chicago.

The 22-year-old was arrested "without incident" after a brief car chase, Highland Park City Police Chief Lou Jogmen said on Monday.

The police had previously searched for the suspect Robert Crimo under high pressure and with hundreds of heavily armed forces.

At least six people were killed in the attack during Independence Day celebrations on July 4 in Highland Park, Illinois, north of Chicago.

Around 25 other people were injured by bullets.

The shooter opened fire on a crowd attending a holiday parade from the roof of a shop, police said.

"Everything indicates that he was discreet and very difficult to see," said a security spokesman, Christopher Covelli.

The attacker apparently specifically targeted the spectators of the parade.

Stage name "Awake the Rapper"

Hours after the attack, police released the identity of the 22-year-old suspect and released a mugshot.

He was initially officially referred to as a "person of interest".

Police warned the man was believed to be armed and "very dangerous".

He was therefore traveling in a silver-colored car.

The suspect's age and name also match a Chicago musician with the stage name "Awake the Rapper".

Massacre on Togetherness Day

The shooting began at 10:14 a.m., police said, sparking panic in the small town on the shores of Lake Michigan, where hundreds of people had gathered to celebrate Independence Day.

Many people initially mistook the shots for fireworks.

"We were preparing to march down the street when suddenly waves of people started running," eyewitness and parade participant Emily Prazak told AFP. "Right before that happened, we had the 'pop, pop, pop.' Heard 'pop, pop' and I thought it was fireworks."

Eyewitness Don Johnson told AFP he heard screams and saw people running with children in their arms.

"We ran into the gas station and stayed there for three hours," Johnson said. "I've seen scenes like this on TV and in other cities, and I didn't think it would ever happen here."

Biden: "Senseless gun violence"

US President Joe Biden was "shocked by the senseless gun violence".

He thanked the emergency services and said he was praying for the injured.

Biden also pointed to a recent, slight tightening of gun laws - a minimal compromise between his Democrats and the opposition Republicans - and emphasized that there was "much more work to be done".

"I will not give up the fight against the gun violence epidemic," the President said.

In the United States there had been a whole series of particularly bloody gun attacks in the past few weeks.

In mid-May, an 18-year-old shot dead 19 children and two teachers at an elementary school in the small Texas town of Uvalde.

Ten days earlier, an 18-year-old shot dead ten people in and outside a supermarket in Buffalo, New York, for racist reasons.

But beyond such particularly shocking incidents, gun violence is a common problem in the United States.

More than 10,000 people have been killed by guns in the country since the beginning of the year, according to the website Gun Violence Archive.

There are also more than 12,000 suicides with pistols, revolvers or rifles.