A Colorado sheriff's deputy has been shot dead, becoming the state's third officer to be killed in the line of duty this year.
El Paso County Sheriff deputy Micah Flick, 34, an 11-year veteran of the force, was investigating a report of a stolen car when he was shot.
Three other officers and a civilian were injured in the shootout in Colorado Springs.
The suspect, Manuel Zetina, a 19-year-old resident of the city, also died.
Governor John Hickenlooper pleaded for an end to violence in a statement.
"With the recent loss of now three deputies and many others injured, there's no denying the grave impact this sequence of shootings is having on our state," he said.
He also asked citizens to pray for Mr Flick's family and those who were injured, adding: "We must also come together to say enough is enough."
Officers were responding to a report of motor vehicle theft when they encountered a suspect and a struggle ensued, Colorado Springs Police Chief Pete Carey told a news conference.
Police say gunfire broke out around 16:00 local time in a residential area of Colorado Springs, about 70 miles (110km) south of Denver.
Three other officers were treated in hospital for non-life threatening injuries.
A man who was passing by was also shot and was undergoing hospital treatment.
Mr Flick, who leaves behind a wife and seven-year-old twins, is the third on-duty officer in only five weeks to be killed in Colorado.
Civilians and officers stood in the freezing cold on Monday night along South Nevada Avenue in Colorado Springs to pay their respects as a procession carried the slain officer to the coroner's office.
The El Paso County Sheriff's officer tweeted a picture of the slain deputy with the caption: "Our Brother Deputy Flick. End of Watch, February 5, 2018".
"Our hearts are broken," the department wrote in another post.
A total of seven officers have been shot in the line of duty in those incidents, according to the Denver Post newspaper.
On 24 January Adams County sheriff's Deputy Heath Gumm, 31 was shot while chasing a suspect.
Douglas County Sheriff's Deputy Zackari Parrish, 29, was fatally shot in an "ambush-style" attack on New Year's Eve, according to investigators.
We are grieving the loss of @EPCSheriff Deputy Micah Flick. Again saying words of condolence, crying tears of sorrow, screaming in frustration at another life taken too soon. 5 weeks, 3 deputies, 3 black bands, 3 broken families, 1 thin blue line that will only get stronger.— Arapahoe Sheriff (@ArapahoeSO) February 6, 2018