City of Boulder, CO

06/25/2026 | Press release | Distributed by Public on 06/25/2026 12:47

Boulder Police Arrest Man Who Attacked Two People with a Knife

BOULDER, Colo. - Boulder Police arrested a man within minutes this morning after he attacked two strangers with a knife.

At 7:54 a.m. officers received a call that a man had attacked a woman with a knife in the 1300 block of Pearl Street. The woman, 44, was walking to work when the man approached her and began hitting her with the knife. She suffered bruises and cuts to her hand. She was able to get away and the suspect then walked up to a man walking to work. He cornered him and stabbed at him but did not make contact. The man, 50, threw his coffee at the suspect and ran away.

The suspect then walked in the opposite direction. Within 10 seconds, officers in the city's Public Safety Information Center found the suspect via surveillance camera. At 7:56 a.m., officers took the suspect into custody at gunpoint.

Further investigation revealed a possible witness that officers are working to identify. If you recognize her below please contact detectives.

Based on interviews with detectives, the suspect said he came to Boulder to hurt people. Detectives believe he targeted strangers who were walking alone and that he was the only suspect.

The suspect has been identified as Marcus Ariel Valles, 35, of Lakewood. He has been charged with three felony counts of attempted murder in the first degree, two counts of felony menacing and one felony count of first degree assault. These charges can change and additional charges are likely.

"This could have been much worse. We will not tolerate anyone coming to our community to do harm. I'm proud of the swift response by both our Public Safety Information Center operators and our Patrol officers who were able to find this man within seconds and arrest him within two minutes of the call coming out," Boulder Police Chief Steve Redfearn said.

Anyone with any information about the suspect or this morning's crime is asked to contact detectives via the Boulder Police tipline at 303-441-1974 regarding case 26-05470.

As in every criminal case, these charges are an accusation, and the defendant is presumed innocent unless or until proven guilty.

Photo of possible witness detectives are trying to identify:

Photo of the suspect's knife:

--CITY--

City of Boulder, CO published this content on June 25, 2026, and is solely responsible for the information contained herein. Distributed via Public Technologies (PUBT), unedited and unaltered, on June 25, 2026 at 18:47 UTC. If you believe the information included in the content is inaccurate or outdated and requires editing or removal, please contact us at [email protected]