About 2,000 people, including U.S. Sen. Michael Bennet and Rep. Jason Crow, gathered Wednesday night to honor victims and survivors of an attack that killed a teenager and wounded eight others at a Highlands Ranch school.

Many students at the event walked out in protest over the event’s pro-gun-control message, then came back and took turns at the microphone.

Students associated with the gun control advocacy group Brady Campaign to Prevent Gun Violence organized the vigil, held at nearby Highlands Ranch High School. Moms Demand Action, a group that advocates for gun control legislation, also had representatives at the event.

Attendees packed a school gym to remember 18-year-old Kendrick Castillo, who was shot and killed trying to tackle one of the shooters at STEM School Highlands Ranch on Tuesday. Authorities have credited Castillo and two classmates with thwarting the attack.

Also in attendance was state Rep. Tom Sullivan, D-Centennial, who lost his son, Alex, in the massacre at a movie theater in Aurora in 2012.

Bennet and Crow, whose congressional district includes STEM, spoke about the need for gun control at the gathering.

Many STEM students who came to the event said they were frustrated to hear politicians speak, and grew angry as the conversation turned to gun control and policy. A large group stormed out of the event in protest. They later returned and demanded an opportunity to speak; some said they didn’t want to be used to promote gun control.

“What has happened at STEM is awful, but it’s not a statistic,” one student told the crowd. “We can’t be used [as] a reason for gun control. We are people, not a statement.”

The crowd cheered loudly in response.

“This was not a vigil. This was purely a political stunt. This is not what we wanted for Kendrick,” said another student.

Some of those who walked out were heard to call for additional mental health services as a way to address mass shootings.

The Brady Campaign later issued a statement saying the vigil was intended to “show solidarity with the STEM School students, teachers and parents,” adding: “We are deeply sorry any part of this vigil did not provide the support, caring and sense of community we sought to foster and facilitate and which we know is crucial to communities who suffer the trauma of gun violence.”

> CLICK HERE for more from 9News.

The Associated Press and 9News contributed.

=

=

=