SEATTLE — A King County judge decided to hold a 15-year-old boy in detention in connection with the Seattle Center shooting that left three dead and four others injured, including a toddler.

Police believe two people were shooting at each other at the annual Bite of Seattle food festival, and a police report filed with the court on Monday stated detectives believe one of the deceased was in a gunfight with the 15-year-old. Police believe there is “at least one other unknown suspect” who was part of the gunfight, according to the police report.

The teen waived his presence in court on Monday. Judge Tanya L. Thorp found probable cause for three counts of first-degree assault and one count of second-degree illegally possessing a firearm, and she ruled the teen will remain in secure detention.

The Seattle Times does not typically name juvenile suspects unless they are charged as adults.

A 19-year-old man and 44-year-old man were declared dead at the scene. A 56-year-old woman was taken to Harborview Medical Center, where she died. A woman, 30, had minor injuries and was treated by paramedics at the scene. A 39-year-old woman was taken to the hospital and has since been discharged. A 23-year-old man who was injured has also been discharged. The 2-year-old boy who was hurt remained at Harborview in satisfactory condition.

Additionally, a 27-year-old man reported to University of Washington Medical Center later that night with a gunshot wound. It remains unclear if he was injured in the Bite of Seattle shooting.

In a police report filed Monday with the court, a police sergeant allegedly followed the gunshots at 6 p.m. Sunday and saw a boy with a handgun firing into the crowd, less than 100 feet from the officer. The sergeant took the boy into custody and found a handgun “on his person,” according to the report.

An “associate” of the teen died from gunshot wounds, according to the report. In the direction the teen had been pointing his gun, officers initially found three wounded people, one of whom had been riding a bicycle, according to the statement.

Assistant Chief Tyrone Davis said Sunday night that investigators do not believe the other suspect poses a threat to the general public, but did not elaborate.

Hong Tran, an attorney for the teen, argued there is insufficient information in the probable cause statement to support three counts of first-degree assault.

“Innocent bystanders were struck,” prosecutor Logan Bryant argued, arguing the teen poses a threat to the community.

Thorp ruled the teen must not contact the Seattle Center or the victims.

The 15-year-old suspect was booked for investigation of firearms violations and first-degree assault, Wilson said.