A woman recognized her brother’s clothes in photos released after a deadly Halloween party shooting in Boulder, Colorado, then checked the family’s Life360 app to confirm her suspicions, according to an arrest affidavit reviewed by Fox News. Her tip led to the identification and arrest of 18-year-old Omar Perez.
Perez is being held without bond on murder and related charges. He is accused in the death of 19-year-old Luca Hanlon, a University of Colorado Boulder student, following a confrontation at an off-campus Halloween party in Boulder’s University Hill neighborhood.
Boulder Police Public Information Officer Dionne Waugh said everyone in the photos and video released by police has now been identified. Police first showed up at the home on Marine Street around 9:58 PM on Halloween night after a noise complaint and issued a nuisance party citation, which sent hundreds of people home. About 90 minutes later, at 11:28 PM, officers were called back to the same address for a report of gunshots.
His sister allegedly spotted the mask in his car
Witnesses told authorities that Perez had been part of the group that left after the citation, but he allegedly returned to the residence with six other people. When they were asked to leave again, Perez and his group reportedly became irate, and a scuffle started in the living room and spilled onto the front porch. One witness claimed Perez was wearing a SWAT uniform and a “Purge” mask.
A resident reportedly put Perez in a headlock, and Perez allegedly pulled out a gun and opened fire, according to the affidavit. One witness told police they heard Perez threaten, “Oh, I could shoot this place up.” Perez allegedly shot Hanlon in the neck and another 19-year-old student in the leg. Hanlon died the next day at Boulder Community Health.
The affidavit states that Perez’s sister saw the photos released by Boulder police and reached out because she recognized her brother’s clothes. She then opened the family’s Life360 app, a location-sharing tool similar to the trackers that showed Las Vegas twins at a random house. The app allegedly tracked Perez arriving at the residence around the time of the shooting and mapped his path afterward through Westminster, Arvada, Keenesburg, and back to Thornton over the next several hours.
The sister also told investigators that Perez allegedly bought a 10mm Glock “on the street” days before the shooting and posted photos of the weapon on Instagram. She claimed it replaced a revolver he “threw in some bushes” after he accidentally shot himself in the calf in September.
The affidavit also noted that Perez and the people with him traveled in a newer red Audi sedan. When Perez later picked his sister up from work, she got into the Audi and noticed a “black purge looking mask” on the floorboard, along with three other people in the vehicle. Perez allegedly told his sister that he and his friends had been beaten up earlier at a party.
Perez was arrested in Thornton. Shannon Carbone, the public information officer for the Boulder County District Attorney’s Office, said he is not a CU student and was not arrested on campus, contrary to some rumors. He faces charges of murder with extreme indifference, first-degree assault, and attempted first-degree murder with extreme indifference. He is presumed innocent unless and until proven guilty in court.
Carbone said the only sentence allowed under law for first-degree murder is life in prison without the possibility of parole, and that additional charges will likely be filed. Perez’s preliminary hearing is scheduled for February 10, 2027.
The University of Colorado Boulder identified Hanlon as a second-year media production student in its College of Communication, Media, Design and Information. His friend Jack Anderson told Denver7, “It doesn’t feel real. He was my best friend. He was always there.” Anderson added, “I would say he was who I aspired to be in life. He was that person.”
Boulder police are asking anyone with information to call 303-441-3333 or submit tips through the department’s Evidence Submission Portal.
Published: Nov 15, 2026 02:15 pm