Thornton man, 18, charged with first-degree murder in shooting death of CU Boulder student

An 18-year-old man charged with first-degree murder walked into a Boulder County courtroom in a red jumpsuit, his hands cuffed and his head down.

Omar Perez is charged with first-degree murder, attempted murder and assault.

Watch the latest update in the video below Thornton man, 18, charged with first-degree murder in shooting death of CU Boulder student, police say

Police arrested Perez, a Thornton man, on Monday for allegedly shooting and killing 19-year-old CU Boulder student Luca Hanlon and hitting another student in the leg. Perez is not a CU Boulder student.

The victims' family and friends sat in front of District Attorney Michael Dougherty during the hearing.

Watch below: 'He was who I aspired to be in life. He was that person', Roommates remember victim of Boulder shooting

'He was who I aspired to be in life. He was that person', Roommates remember victim of Boulder shooting

"This is the first murder we've had in the city of Boulder all year. Boulder is a relatively safe and wonderful place, but no community is immune from gun violence. We also shouldn't just accept that or accept the consequences of it," Dougherty said.

According to arrest documents, a Halloween Party was being held at an off-campus home on Marine Street. It was shut down.

Watch below: CU Boulder student killed, another injured in Halloween party shooting

CU Boulder student killed, another injured in Halloween party shooting, people of interest sought

Arrest documents state Perez and five other people were kicked out of the home before Perez turned back and "pushed his way back" into the home.

A witness said he saw Perez rushing towards someone. The witness told investigators he stepped in and placed Perez in a headlock.

The witness told investigators he then heard popping sounds and saw a gun in Perez's hand. The witness said he backed off and Perez ran out the door.

When Denver7 noted the arrest document reads like Perez's sister is ultimately the one who called in the tip that led to Perez's arrest and asked whether that was true, Dougherty responded.

"The arrest affidavit is a public document, and that's how you've been able to access it. The work by the Boulder Police Department did generate a significant amount of leads and tips, and I'm still encouraging community members, friends, whomever might have information to reach out," Dougherty said.

No bond was set, and the judge issued a protection order. Perez's next hearing is set for 9 a.m. on February 10.

This story was reported on-air by a journalist and has been converted to this platform with the assistance of AI. Our editorial team verifies all reporting on all platforms for fairness and accuracy.