Tyler Boyd Reilly, a former Boulder County Sheriff's Office deputy, was arrested early Monday after firing at the department's headquarters with an AR-15 style rifle. The incident began at approximately 12:02 a.m. on September 28, 2026, when the Boulder County Sheriff's Office Communications Center received a call from a male reporting anxiety.
When the caller phoned back at 12:08 a.m., he made threats toward Boulder County Sheriff's Office facilities, including the Boulder County Jail at 3200 Airport Road and the Sheriff's Office Headquarters at 5600 Flatiron Parkway in Boulder. Sheriff's office personnel determined the calls originated from Reilly, who previously worked in both the jail and patrol divisions before resigning on May 25, 2024, in lieu of termination for cause.
After learning of the threats, deputies were stationed at the Headquarters, Jail, and Communications campuses. At approximately 1:08 a.m., a Boulder County Sheriff's Office sergeant observed Reilly at the front door of the Sheriff's Office Headquarters, armed with an AR-15 style rifle. He fired multiple rounds at the entry area but did not gain entry, according to the sheriff's office. Personnel were inside the building at the time. Deputies confronted Reilly outside and took him into custody without incident.
During the investigation, authorities learned that Reilly also stopped at the Broomfield Police Department at 7 Descombes Drive and fired rounds at multiple police vehicles. There have been no reported injuries in Boulder or Broomfield counties, the sheriff's office said.
Reilly has been charged with attempted first-degree burglary, felony menacing with a deadly weapon, criminal mischief, and prohibited use of weapons in connection with the Boulder County Sheriff's Office incident. He also faces charges of criminal mischief for damage between $100,000 and $1,000,000 connected to the Broomfield Police Department incident, as well as second-degree assault on a peace officer causing bodily injury from an incident at the Boulder County Jail after his arrest.