Police say the shooting happened during a fight between two groups which police attempted to break up. Police say the officer was off-duty.
The officer, later identified as 32-year-old Celena Hollis, was shot in the head.
Denver Police Chief Robert White says they have 21-year-old Rollin Oliver in custody. Oliver is the accused shooter.
The shooting occurred shortly after the Jazz in the Park concert series ended around 8 p.m. Hundreds attended the event, including families and children. Mayor Hancock's wife and child also attended.
A 9NEWS employee, attending the concert, heard the shooting and saw several people run towards the south side of the park.
Police say Hollis was a single mother and had been with the department since 2005. She previously served with the Detroit Police Department.
"I don't know what you say to a 12-year-old young lady who just lost her mother in the line of duty," Denver Mayor Michael Hancock said Monday morning during a press conference.
She had helped with the Jazz in the Park concert series for several years. Police say Hollis was president of the Denver Black Police Officers Association. Officer Hollis has been recognized numerous times for her outstanding performance and service to the community.
Witnesses told 9NEWS an ambulance was on scene within five minutes and transported Hollis to Denver Health.
Denver Mayor Michael Hancock and Denver Police Chief Robert White made a statement outside Denver Health Sunday night.
They called Hollis dedicated and a leader in the department. Mayor Hancock says the city will come together.
"We will put our arms around this family and this child, and make sure they know there is a city that absolutely loves them," Hancock said.
"She was an amazing person with an engaging smile who was well liked and respected by her colleagues and the community she served. She will be missed," a press release said Monday morning.
Police were seen searching a Dumpster near a lake Sunday night. Police said Monday morning they found a gun but did not confirm if it is the murder weapon.
Police are asking those who witnessed the shooting, or even took video of the incident, to contact them. Call Crime Stoppers at 720-913-7867.
Gov. John Hickenlooper ordered flags be lowered to half-staff on all public buildings statewide on Monday, June 25 in honor of Denver Police Officer Celena Hollis.
A memorial service for Hollis will be held Saturday at 11 a.m. at the
Denver First Church of the Nazarene on 3800 E. Hampden Avenue Englewood, CO 80113.
Interment will be at Fairmount Cemetery on 430 S. Quebec Street,
Denver, CO 80247.
Donations for Hollis' daughter and family can be made to -
Celena Hollis Memorial Fund
Account Number 23012705
Rocky Mountain Law Enforcement FCU
700 W. 39th Avenue
Denver, CO 80216
NOTE: South Metro Professional Firefighters will be hosting their fourth annual memorial golf tournament on Monday. The money raised will go to families of firefighters and police officers killed in the line of duty. Some of the money raised today will go to Denver Police Officer that lost her life yesterday. Contact Jon Adams at 303-396-5608 for more details.
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