Denver office shooting victim had filed for divorce from gunman

A murder-suicide in a Denver office building Tuesday afternoon drew a massive police response and left workers rattled.

Police responded Tuesday afternoon to reports of an active shooter at the Alliance Center in Denver, Colorado. The building houses several left-leaning political and environmental organizations, according to The Denver Post.

Jake Williams, executive director of Healthier Colorado, sent a tweet to staff Tuesday afternoon.

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The Denver Police Department confirmed that a man with a gun was present and quickly cleared everyone out of the building.

Police confirmed that one victim was shot several times by the gunman and was taken to the hospital in critical condition, where she died Wednesday morning. The shooter was found dead from a self-inflicted gun shot.

The victim, identified by KCNC as Cara Russell, 52, had filed for divorce from the shooter in April. KCNC identified the gunman as Mickey Russell, 58, who was believed to be mentally unstable but had a limited criminal history.

Russell was the executive director of the Colorado Recycling Association.

Authorities continue to investigate the incident.