Eight people were injured, including an 8-year-old boy who was struck in the head and was in critical condition, after a shooter opened fire at a splash pad in a Detroit suburb where families gathered to escape the summer heat.

Law enforcement tracked a suspect to a home, where the person died by suspected suicide, authorities said.

At least two of the victims were children, officials said. Authorities initially said they believed as many as 10 people had gunshot wounds from the shooting in Rochester Hills, but that number was lowered later on after they checked with area hospitals.

Oakland County Sheriff Mike Bouchard said a suspect had been contained in a home nearby, and law enforcement had the home surrounded. There was no known connection between the gunman and the victims, he said.

The shooting happened just after 5pm local time in the town of Rochester Hills. Bouchard said it appeared to be random, with the shooter driving up to the park, walking to the splash pad and firing as many as 28 times, stopping multiple times to reload.

A handgun and three empty magazines were recovered, the sheriff said.

Police cordoned off the scene of the shooting with tape, and dozens of yellow evidence markers lay on the ground among colourful folding chairs.

In a social media post, authorities said there was still an active crime scene and asked people to avoid the area. Bouchard said it was safe for those sheltering in the park to head home.

It was not immediately clear if other people or weapons were inside the home with the possible suspect, Bouchard said, and law enforcement officials were trying to make contact with him.

The victims were taken to hospitals, and their conditions were not immediately known.

Rochester Hills is about 24km south of Oxford, where in 2021 a 15-year-old fatally shot four high school students.

Police respond to the scene of a shooting at the Brooklands Plaza Splash Pad. The Oakland County Sheriff’s Office says there are “numerous wounded victims” after police were called for an active shooter. Photo / WXYZ via AP

Bouchard said Saturday’s shooting is “a gut punch” for the county.

“We’ve gone through so many tragedies,” the sheriff said. “You know, we’re not even fully comprehending what happened at Oxford. And, you know, now we have another complete tragedy that we’re dealing with.”

Michigan Governor Gretchen Whitmer said on the social platform X that she was heartbroken to learn of the shooting and was in touch with local officials.