CHICO, Calif. — The suspect accused in Monday's shooting at the Butte County Library in Chico has been identified as 18-year-old Chico resident Bradley Scott Sayer.

Sayer has been arrested and booked into the Butte County Jail on two open counts of murder following a June 22 shooting that left two adults dead and a juvenile injured, according to a news release.

The Chico Police and Fire Communications Center received multiple 911 calls at approximately 5:12 p.m. reporting gunshots and screaming inside the library. During a news conference following the incident, Chico Police Chief Billy Aldridge said dispatchers received an open 911 line where callers could hear "gunshots and people screaming."

Several Chico police officers and surrounding agencies responded to what Aldridge described as an active shooter incident. Officers arrived at the library at approximately 5:18 p.m. and quickly formed an entry team.

"As they made entry, the suspect fled out the back of the library where Chico police officers had already set up perimeter and were able to take him into custody shortly thereafter," Aldridge said.

According to investigators, Sayer was taken into custody without incident and no shots were fired between the suspect and responding officers.

Authorities confirmed two adult victims died in the shooting. A juvenile victim was transported to Enloe Hospital with non-life-threatening injuries.

"The incident this evening was obviously very sad, traumatic for a lot of people, very traumatic for our community," Aldridge said. "My heart's prayers go out to the families of those involved in this incident here tonight."

The Chico Police Department, working alongside investigators from the Butte County Sheriff's Office and the Federal Bureau of Investigation (FBI), continues to investigate the attack. Detectives are conducting interviews, collecting evidence and reviewing the circumstances surrounding the shooting.

Investigators have determined Sayer acted alone and found no indication he had any prior relationship with or connection to the victims inside the library.

According to the Chico Police Department, investigators believe Sayer's motivation was driven by a desire to carry out a shooting similar to the 1999 Columbine High School massacre.

Aldridge emphasized that authorities do not believe there is an ongoing threat to the public.

"We don't feel like there's any further threat to the public," Aldridge said. "We have one person in custody and further investigation is occurring to see if there's any further people involved in this case."

The investigation remains active as detectives continue gathering evidence and interviewing witnesses. Authorities are asking anyone with information related to the case to contact the Chico Police Detective Bureau at (530) 897-5820.

The incident prompted a large-scale response involving local, state and federal agencies, including the Butte County Sheriff's Office, California Highway Patrol, California State Parks and Recreation, Cal Fire, Butte College, the FBI and the California Department of Corrections and Rehabilitation.