Three students were hospitalized in critical condition after a shooting at Evergreen High School, the Jefferson County Sheriff’s Office said Wednesday. One of the hospitalized students is the suspected shooter.

The shooting was reported shortly after noon and is believed to have taken place on school grounds but not inside the building, Jacki Kelley, a sheriff’s office spokesperson, said in a press conference. It was not immediately clear how the shooting suspect was injured, but Kelley said she did not “believe law enforcement fired any rounds today.”

“There is no danger. No one needs to be locked down,” Kelley said. “The school has been swept, so now the hard work begins. We have to protect our crime scenes, and we have to put together a case.”

Colorado Governor Jared Polis said in a statement that he was “closely monitoring” the situation and that state troopers were assisting in the response.

“Students should be able to attend school safely and without fear across our state and nation,” Polis said. “We are all praying for the victims and the entire community.”

The Democratic state lawmakers who represent the Evergreen area said Wednesday that they were shocked and outraged by the shooting.

“I am horrified by the shooting at Evergreen High School, and my heart breaks for the students, educators, families and school personnel whose start to the school year has now been marked by inexplicable violence and harm,” said Representative Tammy Story of Conifer. “I am hoping for the swift recovery of the victims, and my thoughts are with them and their families.”

“I am heartbroken by the news of the shooting at Evergreen High School and angered at another senseless act of gun violence in our state,” said Senator Lisa Cutter. “Schools need to be safe places, and this tragedy is yet another reminder that we must do better to protect our kids.”