CENTENNIAL - An apartment fire that injured eight people early Monday morning may be the work of an arsonist, the Arapahoe County Sheriff's Office said.

An arson dog was brought in to inspect the scene Monday and found physical evidence that led them to believe it was arson. They believe the fire was started near Building G. The sheriff's office did not say if the dog found anything. Some evidence was also sent to the Colorado Bureau of Investigation for analysis.

Authorities are asking residents to help them investigate the arson. If residents have video or pictures, the authorities want to see both.

Flames broke out around 1 a.m. at the Copper Terrace Apartments at 6550 S. Dayton St., according to South Metro Fire. Eight people were injured, including one critically.

Neighbors used sheets as ropes, mattresses and a pickup truck to help save people stuck inside. Residents in the apartment jumped out windows to try and save their lives.

Lenise Ruff got second-degree burns on her hands, but her roommate has two lumbar fractures. They both had to jump from the third story to get out safely.

GALLERY: 8 injured in Centennial apartment fire

"I just wanted us to get out alive," Ruff said. "I was like, 'you know, if I jump, I may get crippled, but I'm gonna jump, and I'd rather be alive and crippled than burning.'"

Ruff is getting married in a week. Her roommate is her maid-of-honor, so she's hoping she's better by the time they tie the knot. She joked that she was happy Photoshop exists so they can make her hands look pretty in her wedding photos. Her wedding dress was at her parents' house so she only lost her wedding shoes.

Warren Ratcliff lives in the apartment complex and as soon as he heard the fire alarm going off, he sprung into action.

"The only thing I could think of is we had some people up there, a little baby and a female, of course, the husband, but we need to get them out," Ratcliff said.

Ratcliff along with Bryan Schoff helped the people get out. Ratcliff drove his pickup truck to the edge of the apartment complex. Schoff helped grab a mattress to put in the back of the truck. The two of them then tied sheets together for a makeshift rope.

Their actions helped get a family of three, including a baby, out of the apartment.

"There was a lot of smoke. I couldn't see three feet in front of me," Schoff said.

Schoff, who is a former National Guardsmen, also helped catch a person who jumped out of a window.

"I think this community is incredible," said South Metro Fire spokesperson Becky O'Guin. "They generally do come together when people are in trouble and help out, I think it was great for them to help each other out."

Four fire departments responded to the apartment complex.

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