Authorities in Colorado are investigating a threat to police officers from an unknown individual.

The disturbing 911 call came in Sunday at around 6p local time to the Aurora police department. Officers there and in nearby Denver are on high alert.

“It’s time that you guys know we are no longer playing around with the police departments. Aurora and Denver, we are about to start striking fear shooting down all cops that we see by their selves. This will go for the sheriff’s department. You guys are evicting innocent people. Let us catch you by yourself and it’s shots fired," the caller said.

According to KDVR, officers in Aurora were shot at later on Sunday night after being called to a scene. It's unclear if the two events are related.

A Denver police detective said that anti-police sentiment is present throughout the country, and no police department is immune to the growing threat.

Watch the report above.

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