One student was killed and eight others were wounded when two shooters opened fire at a K-12 school outside Denver on Tuesday.

The suspects, a juvenile female and an adult male, are in custody after the shooting at STEM School Highlands Ranch, a charter school in Highlands Ranch, Colo., Douglas County Sheriff Tony Spurlock said at a press conference Wednesday morning. Law enforcement authorities initially incorrectly identified the juvenile shooting suspect as male.

The coroner’s office identified the student who died in the shooting as Kendrick Ray Castillo, 18. “He was the best kid in the world,” his father John Castillo told the Denver Post.

John Castillo said the coroner told him his son was fatally shot after he charged at one of the gunman in the school.

“I wish he had gone and hid, but that’s not his character. His character is about protecting people, helping people,” he told the newspaper.

Spurlock, the sheriff, said that all the victims are 15 years old or older. By Wednesday morning, three of the victims were still in intensive care at hospitals in the area. The rest of the victims had been released.

Tuesday’s violence was just the latest mass shooting in the Denver suburbs. Highlands Ranch is a suburb of Denver, and the school is roughly 14 miles from the city center. The school’s website says that about 1,800 students attend the school.

The school is about eight miles from Columbine High School, where 12 students and one teacher were murdered on April 20, 1999. Several days before the 20th anniversary of the Columbine shooting, schools throughout the Denver area were closed after a young woman, who was said to be infatuated with the Columbine attack, threatened schools in the area. The woman later died by suicide.

“I’ve got four kids in this school system, my wife’s business is less than a mile from here, I grew up in these parts,” 18th Judicial District Attorney George Brauchler said at Wednesday’s press conference.

“And if you had suggested to anyone behind me or in this room that within 20 years and 20 miles, we would have dealt with Columbine, the Aurora theater, Arapahoe High School, the shooting of Zack Parrish and four other deputies, we’d have thought you mad. And yet, here we are again.”

In addition to Columbine, Brauchler referenced the July 2012 shooting at a movie theater in Aurora, Colo. that left 12 dead and dozens wounded; the Dec. 13, 2013 shooting at Arapahoe High School in which a heavily armed student fatally wounded a classmate before taking his own life; and the Dec. 31, 2018 killing of Douglas County Deputy Zack Parrish in an ambush that resulted in four deputies and two bystanders being wounded.

In addition, there was a November 2017 shooting at a Walmart in Thornton, Colo. in which a gunman walked into the store and killed three customers.

At STEM Academy, the two shooters entered through the middle school entrance, where there are no metal detectors, and walked “deep inside the school” and started attacking students at around 2 p.m., Spurlock said. People in the school “almost immediately” called 911, and police arrived at the school about two minutes later. Undersheriff Holly Nicholson-Kluth said that police were on the scene “almost immediately” because there is a police substation a block from the school. She said that police could hear gunshots as they entered the school.

Students escorted on school bus in front of STEM School Highlands Ranch after a shooting. May 7, 2019. Hyoung Chang/MediaNews Group/The—Denver Post via Getty Images

The school does not have a school resource officer, but has one armed security guard hired from a private company. Spurlock said one of the suspects was restrained by the time the deputies came into contact with them. The suspects were taken into custody without any exchange of gunfire with authorities.

In addition to reports of Kendrick Castillo’s heroics during the shooting, the local Marine Corps. recruitment office said student Brendan Bialy, who plans to join the Marines after graduation, helped to subdue one of the shooters.

“Brendan’s courage and commitment to swiftly ending this tragic incident at the risk of his own safety is admirable and inspiring. His decisive actions resulted in the safety and protection of his teachers and fellow classmates,” a statement from the Marines said.

Spurlock said two handguns were used in the shooting, but did not release more details about the weapons that were used or how they were obtained. Spurlock also declined to answer questions about a potential motive in the shooting.

Nicholson-Kluth said that crimes like this are uncommon in Highlands Ranch.

“This is a good community. It’s usually very quiet. Low crime rate. So this is unusual for us,” said Nicholson-Kluth.

Jennifer Brown, a reporter from the Colorado Sun, tweeted a picture taken at the crowded parent reunification center.

The White House released a statement about the shooting on Tuesday night.

“Our prayers are with the victims, family members, and all those affected by today’s shooting at STEM School Highlands Ranch in Littleton, Colorado,” the statement said. “Tragically, this community and those surrounding it know all too well these hateful and horrible acts of violence. The White House has been in communication with state and local officials, and the President has been briefed and continues to monitor the ongoing situation. We offer our full support to local law enforcement and first responders and thank them for their heroism.”

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