Police are seeking two persons of interest after gunfire erupted inside a University Hill home late Halloween night.
BOULDER, CO — A 19-year-old University of Colorado Boulder student was killed and another 19-year-old student was critically wounded in a shooting inside a University Hill home late Saturday, after police had earlier broken up a large Halloween party at the residence.
Boulder police said officers began receiving reports of gunfire at about 11:28 p.m. Oct. 31 from a home in the 700 block of Marine Street, near Seventh Street. Officers arrived in less than two minutes and found two men with gunshot wounds. Both were taken to a hospital, where one died early Sunday. The other remained in critical condition. Authorities had not released either student’s name as of Sunday evening, and the Boulder County Coroner’s Office was expected to identify the student who died after family notification.
The shooting followed an earlier police response to a noise complaint at the same home. Police Chief Stephen Redfearn said hundreds of people had been attending a party that included a live band. Officers contacted the organizers after receiving the complaint and later issued a nuisance-party citation. One highly intoxicated person was also taken into protective custody, according to accounts from the police briefing. The large gathering then dispersed, although a smaller group remained inside the home.
Investigators believe another group later tried to force its way into the residence. A scuffle followed, and shots were fired inside the home, striking the two students, police said. Authorities have not publicly said what led to the confrontation, whether the people who tried to enter had attended the earlier party or who fired the shots. No arrest had been announced Sunday.
Detectives interviewed about 20 witnesses overnight and were reviewing video and other evidence from the scene. Police released photographs and video of two men described as persons of interest and said investigators urgently want to speak with them. Authorities have not identified either man as the shooter or said that either has been accused of a crime.
Redfearn said investigators had no information indicating that the person or people responsible remained in Boulder. Police nevertheless increased their presence around University Hill as the investigation continued. CU Boulder police also established a perimeter along the west side of campus after the shooting and helped Boulder officers interview witnesses, many of whom were students.
The Halloween gathering had been registered through a program involving CU Boulder and Boulder police that allows party organizers to receive warnings when noise complaints are made, according to officials cited by Boulder Reporting Lab. Organizers complied with instructions to shut down the party after officers arrived, the report said. University officials said they were not aware of any formal university affiliation with the gathering, including a fraternity connection.
Redfearn described the shooting as an unusually serious act of violence for Boulder and said it marked the city’s first homicide of 2026. “Our community deserves to feel safe, and we will not accept this kind of violence in Boulder,” he said in a police statement. He said investigators were working to identify those responsible and determine exactly what happened inside the home.
University of Colorado Boulder Police Chief Ashley Griffin and Boulder County District Attorney Michael Dougherty joined Redfearn at a Sunday morning news conference. Dougherty said investigators had already made progress but stressed that authorities still needed information from people who were at the gathering or saw what occurred before the shooting. Police also sought photographs and video taken at or near the party that could help establish the sequence of events.
The investigation remained active Sunday evening. Police had not announced a suspect, arrest or motive, and the identity of the student who died had not been publicly released. Authorities said additional information would be released as the investigation develops, while Boulder and university police planned an increased presence around the University Hill area.
Author note: Last updated Nov. 1, 2026.