A 911 caller made death threats against police in Aurora, Colorado on Sunday night. Police are said to be on high alert after the threat.

The call came in to a 911 dispatcher Sunday evening around 6pm. Fox31 obtained audio of the call. After the dispatcher asks the caller to state the emergency, a male voice says, “It is 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.”

Later the same night Aurora police were called to a scene where they were shot at by unknown assailants. Police are still investigating the incident and have not determined whether the threatening call and the shooting were connected.

The threats are being seen by some as part of a wave of anger directed at police nationwide. Denver police Detective Nick Rogers told Fox31, “It’s going on nationally. It’s going to come here. There’s nobody that’s immune to it. Nobody in law enforcement.”

“People make threats to police all the time, but very rarely do we get anything involving folks wanting to shoot at the police,” Aurora Police Association President Bob Wesner told Fox31.

The 911 threat comes over the same weekend anti-police graffiti turned up in various locations across the country. In Houston, Texas emoji-style images of a policeman with a gun aimed at his head have been spray painted in locations around the city.

Also over the weekend, graffiti reading “F–k the police” was found in several locations around the city of San Antonio. The same message has been appearing as graffiti in Lakeville, Minnesota for the past two weeks.

Police in Webster, NY were alerted Saturday about graffiti spray painted on the street which read, “Kill the cops, WPD.”