WESTMINSTER, Colo. — Investigators are taking a start-from-scratch look at a 20-year-old cold case where three people -- Paul Skiba, his 9-year-old daughter Sarah and his employee Lorenzo Chivers -- disappeared from a Westminster storage lot.

Their bodies have never been recovered, but police said they believe they were murdered after dropping off a moving truck at the lot in Westminster on Feb. 7, 1999.

"Every February is heartbreaking for me, and especially so this year since I’ve been reliving the horrendous murder of my 9-year-old daughter, Sarah Skiba, for 20 years now," said Michelle Russell, Sarah's mother, in a statement. "The pain of her loss has not been any easier with the passage of time."

According to police, Sarah had tagged along with her dad when he went to work that day at his moving business -- Tuff's Moving at 7010 Raleigh St. 

Paul Skiba
Courtesy Westminster PD

Chivers was an employee there. Paul Skiba's other associates were Alex Santovena, Jerry Bybee, Jesus “Manuel” Santovena and Jake Bustillos, according to police.

Lorenzo Chivers
Courtesy Westminster PD

Around 8:30 a.m., Sarah accompanied her dad and Chivers as they worked moving people. They arrived in Thornton at around 10:30 a.m. for a moving job, and had lunch afterward in Lakewood, at about 12:50 p.m., according to Westminster police.

Sarah Skiba
Westminster Police Department

The three went to another moving job in Morrison, another in the Golden area and then returned to the Tuff's Moving yard (pictured below, as seen in 1999) at 6:15 p.m. Sarah made one final phone call, at 6:22 p.m., according to investigators.

Tuff's Storage as seen in 1999
KUSA

"I can’t think about the fact that Sarah would be 29 years old now: a grown woman, possibly with a family and children of her own," Russell said. "But instead, her life was taken away and I have a hole in my heart that can never be filled."

All three were then murdered, either at the truck yard or at a second location, and detectives said they believe their bodies were removed from the yard in a moving truck to an unknown location.

Investigators at the time of the murders found blood evidence from Paul and Sarah Skiba at the Tuff's Moving facility.

Sarah Skiba
Courtesy Sarah Skiba

Days later, on Feb. 17, 1999, a vehicle belonging to Chivers was located several blocks away from the moving and storage facility at the apartment complex parking lot of 3809 68th Ave. in Westminster, according to police.

Days after that, on Feb. 27, 1999, a vehicle belonging to Skiba was located in an apartment complex parking lot at 3129 Arkansas Ave. in Denver, according to police.

In the last five years, detectives have interviewed two additional witnesses and resubmitted DNA evidence, but the efforts have not provided enough evidence to solve the murders.

"There are too many people who are remaining silent about this for too long – the murder of a 9-year-old girl," Russell said in her statement. "Twenty years is an insane amount of time to not know what happened to your child. Please be a decent human being and come forward with your information, anonymously if you have to. End the silence and help bring Sarah home."

Anyone with information is asked to call Westminster Police at 303-658-4360 or Crime Stoppers at 720-913-7867. Crime Stoppers callers can remain anonymous. A reward of up to $4,000 is being offered.

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