The shooting was described by Sheriff Tony Spurlock as an "ambush-type attack". "They are very tough cases", UW Police Chief Mike Samp said. "And they all went down nearly within seconds of each other".
"He knew we were coming", Spurlock said.
The gunman continued to fire as additional officers arrived at the complex. He's survived by a wife and two young children. He was hit multiple times.' .
The sheriff did not release any details about the weapons and ammunition used except to say the suspect had a rifle.
Adding, 'We will take care of Zack's family... and make sure we can get through it on the other side'.More news: Messi, Suarez score as Barcelona thrash Levante
The officers were all shot and "went down within seconds of each other", but only four of them were able to "crawl to safety", Spurlock said.
One deputy was killed and six other people injured, including four deputies after a shooting at an apartment complex in Colorado Sunday. "This is Colorado. Everybody has a gun", Mr Spurlock said.
"I can't tell you how hard it is to sit down with a spouse of a deputy who has been killed n the line of duty", the haggard-looking sheriff said at a news conference later Sunday. The roommate is cooperating with authorities, according to the sheriff.
Riehl was known to law enforcement, Spurlock said.
According to a letter sent to faculty and staff in November, Riehl posted "rambling, nonsensical messages on his Facebook page" that specifically mentioned the school. "He was in our class", Robert Butler, the lead instructor of the company where the suspect took the course told the New York Times. "He didn't show any signs of being violent or unstable", Butler said.
Photos of Riehl and his vehicle were attached to the email.More news: LSU RB Derrius Guice announces he's leaving early, declares for NFL Draft
There is a fund for fallen officers in Douglas County. The Libertarian Party of Colorado says it had no contact with him.
Douglas County Deputy Zackari Parrish, 29, was killed in a hail of gunfire after the gunman began firing on police from a bedroom inside an apartment as they responded shortly after 5 a.m.to a disturbance at the Copper Canyon Apartment Homes.
It was not immediately clear why the incident had escalated, Spurlock said.
Police were called to Riehl's apartment Sunday for a dispute between Riehl and someone else at the apartment building.More news: Packers reportedly to consider former Bills GM Doug Whaley for same role
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