The suspect was arrested after the deadly gun attack at a US National Day parade near Chicago. The 22-year-old was caught “without incident” after a brief car chase, Highland Park City Police Chief Lou Jogmen said on Monday.

The police had previously worked under high pressure and with hundreds of heavily armed forces after the suspect Robert E. Crimo III. wanted. Crimo was then caught by a police blockade. He tries to flee in his silver Honda but was stopped.

Little is known about the perpetrator. What we do know: The 22-year-old describes himself as a musician and appears in internet videos with the stage name “Awake the Rapper”. In these videos, he acts as an animated cartoon character and shoots guns. In one video, he lies face down on the ground in a pool of blood, surrounded by police officers. His Facebook and Twitter accounts were temporarily switched off after the arrest.

The suspect’s uncle told CNN he had seen no signs of such an attack in his nephew before. “My heart is broken,” Paul A. Crimo told the broadcaster. He expressed his condolences to the victims and their families.

At least six people were killed in the attack during Independence Day celebrations 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.

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 over and over again on TV and in other cities, and I didn’t think it would ever happen here.”

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.