An 18-year-old male student was killed, multiple others injured and two suspects were in custody in the shooting at the STEM School in Highlands Ranch, Colorado on Tuesday afternoon, according to the Douglas County Sheriff's Office.
The victims' names have not been released.
Douglas County Sheriff Tony Spurlock said the suspects – a juvenile and an adult – were believed to be students at the school. Spurlock said there were no other suspects in the case, but authorities were still investigating at the scene.
According to a source with knowledge of the investigation, one of the suspects is an 18-year-old senior who was a student at the school. According to a criminal background check, his only prior run-ins with the law include citations for careless driving and driving an unsafe vehicle.
A source told Scripps affiliate KMGH-TV in Denver that investigators were using a bomb robot near one of the suspect's vehicles because tactical gear was found inside. Authorities had found the vehicle in the parking lot of the school and were working to obtain search warrants for the car and the suspects' homes.
At 6:30 p.m., law enforcement officers were at a home believed to be linked to the 18-year-old suspect, near West Highlands Ranch Parkway and West Wildcat Reserve Parkway in Highlands Ranch.
Spurlock said eight students were injured in the shooting and they were all 15 and older.
Two of the victims were in serious condition at Littleton Adventist Hospital, officials said, and three had been released from the hospital. One victim was in good condition at Children's Hospital. Two other victims were at Sky Ridge Medical Center and listed as "stable," but their conditions were unclear.
Spurlock said the suspects walked into the building, "got deep inside the school" and shot at students at two separate locations. The shooting was reported shortly before 2 p.m., and deputies arrived about two minutes later and engaged the suspects, taking them into custody, Spurlock said.
"I believe the quick response of officers helped save lives," Spurlock said. "A quick response eliminates a lot of this issue right off the bat."
The STEM school, which has about 1,800 students from kindergarten through high school, is located off South Ridgeline Road and Plaza Drive in Highlands Ranch.
The school did not have a School Resource Officer assigned to the building, but it did have private security, Spurlock said.
Department of Homeland Security, FBI and ATF agents also responded to the school to help with the investigation.
The school was placed on lockdown after the shooting, and parents were being directed to meet their children at Northridge Rec Center at 8800 S. Broadway.
Kelley Paulson, the mother of two students at STEM School Highlands Ranch, spoke to KMGH about what she knows about the shooting and said she was still waiting to hear about one of her children.
"I got a text from a friend who was actually in there," Paulson said. "She said 'guns, shooting, oh my god, oh my god.' And she could hear them and that's how I first knew. The next thing I know, I heard my son, who is calling me because all of the kids who were in middle school...all immediately ran out of the building."
Paulson's son, Christian, said he was in study hall at the school when he saw "a bunch of kids running out and saying 'School shooter, school shooter!'"
"And I'm like, what? Is this real or fake? And then I just went after them," Christian Paulson said. "And apparently, this is all real. And I tried to run with my life, but I'm out of breath."
President Donald Trump had been briefed on the shooting, and the White House was in contact with Colorado officials.
“Our prayers are with the victims, family members, and all those affected by today’s shooting at STEM School Highlands Ranch in Littleton, Colorado," White House Deputy Press Secretary Judd Deere said. "Tragically, this community and those surrounding it know all too well these hateful and horrible acts of violence."
Sen. Cory Gardner released a statement, saying he was "heartbroken by the horrific and senseless acts of violence today" at the STEM school.
"The safety and comfort of our schools should never be taken away," Gardner said.