Hollis, 32, was shot in the head during a fight between two groups, which police attempted to break up. Police say Hollis was off-duty. The shooting occurred shortly after the Jazz in the Park concert series ended around 8 p.m. on Sunday.
"As a mother, she wanted to set that example for her daughter in her life. She wanted to live out being a contributing member of a community," said Rachel Sprague, volunteer program manager at Denver Kids Inc., a nonprofit that works with the students from Denver public schools kindergarten through 12th grade.
The employees and volunteers there help kids in at-risk environments, making sure they graduate and become successful members of our society.
Hollis started volunteering with Denver Kids Inc. in 2009, a three-year commitment. She also tried to recruit others to help.
"Her work as a police officer often put her in circumstances where she dealt with kids - as she described - kind of have fallen through the cracks, who didn't have a positive role model or who have kind of ended up on the wrong side of the law" Sprague said. "Her intention was really to be proactive and to engage in the Denver community outside of her work in a way that she could provide a positive role model for the young kids in this community."
On Tuesday, 9NEWS looked for people in Hollis' life who could talk about her life, her work and her loves. 9NEWS reached out to the victim's family, but the family was not ready to talk.
Colleagues at Denver Kids Inc. wanted to share what impact Hollis had on their lives and the life of a girl Hollis was matched with in 2009.
"Celena was a multi-faceted human being," said Deborah Dawson-Thomas, educational counselor for Denver Kids Inc. "[She] found ways to give back. I want them to know there are police officers like her out there that just are so compassionate, and the reason why they do what they do is because they're peace officers, right? So she kept the peace at work, she kept the peace in our community by being a part of Denver Kids Inc."
Dawson-Thompson says Hollis left a hole in the heart of many people who knew her.
"I want her family, her daughter, her parents to know - because they may not know - how extraordinary she was in that other part of her life. I'm sure they do, but she was," Dawson-Thompson said.
Hollis was a Detroit police officer for about four years before moving to Denver.
Detroit Police told 9NEWS she worked downtown for a couple of years with Officer Courtney Jordan. Hollis was like an ambassador of sorts for the City of Detroit, helping not only the residents but also visitors to the city.
"No matter where you go, once you become a member of the Detroit Police Department, you will always be one of Detroit's finest," Detroit Police said.
"Losing one of Detroit's Finest in the line of duty is always very difficult and challenging," Detroit Chief of Police Ralph L. Godbee, Jr. told 9NEWS Tuesday morning. "Although Police Officer Celena Hollis had moved on from the Detroit Police Department to serve with the Denver Police, all of us who have worked along side her are saddened by her passing. She joined the Detroit Police Department on May 14, 2001 ... On behalf of the Detroit Police Department, I want to express my heartfelt sympathy and prayers to the family, friends and colleagues of Denver Police Officer Celena Hollis."
Officer Jordan told 9NEWS' affiliate in Detroit that he got the call about Hollis' death at early Monday morning.
"I was shocked; I was stunned, and I couldn't believe it," he said. "I didn't want to believe it. I still don't want to believe it as I stand here now."
"You knew if you were working with Celena, you were OK," Jordan said. "You knew Celena was going to make sure you made it home. She worked with a smile; she worked with a fire, and the desire to get the job done."
Hollis was very close to her parents and siblings, according to Jordan.
"Myself, along with all the Detroit police officers that she had the opportunity to work with, will all remember Celena as a very warm, compassionate, fiery, smiling, loving her job, loving life, loving her daughter more than anything in the world and doing anything to take care of her daughter," Jordan said.
Hollis 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. 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. She later died at the hospital.
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.
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 Ave. in Englewood. Interment will be at Fairmount Cemetery on 430 S. Quebec St. in Denver.
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: In support of the Denver Police Department, we, Team Heating and Air Conditioning, owner William Doyle and Avalon Electric, owner Kyler Carje installed a 5 ton Air Conditioner in the home of fallen Officer Celena Hollis. Our sympathy and prayers go out to the family and friends of Office Hollis during this terrible time in their lives.
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