Seven people were shot and wounded, three of them critically, at a park in a suburb of Tacoma, Washington, on Wednesday evening, police said.

Officers found a “very hectic scene” when they responded to calls reporting shots fired at Harry Todd Park in Lakewood just before 8 pm, Lakewood Police Sgt. Charles Porche told KOMO-TV. He said medics transported five people to hospitals and two others got to hospitals on their own. The Seattle Times reported that Porche said three people were in critical condition.

Investigators don't know how many shooters were involved or whether the victims were targeted, he said. No arrests had been made as of Wednesday.

More than 100 people were at the park next to American Lake when shots were fired, Porche said.

“We've had these couple days here where the sun finally came out and it's been a gorgeous time for people to get out and enjoy the park, the lake and then you have something like this that happens,” he said. “It is one of the great tragedies, right? You don't want anybody to get shot and then you end up with seven different victims that happen out of this act of violence that, so far, we don't know why.”

The shooting comes days after a Memorial Day shooting at a Philadelphia park that killed two people and injured nine.