Police in Colorado announced the arrest of a man late Monday who they said sexually assaulted and strangled a 20-year-old woman before lighting a pair of fires in her home and driving off in her car.
Joseph Curl, 29, was arrested Monday afternoon after he volunteered to go to the police station to be interviewed about the death of Linnea Dick, a community college student whose body was discovered when firefighters responded to a 911 call about a fire at the house she shared with her boyfriend late Friday morning.
Fort Collins police spokeswoman Rita Davis confirmed Curl's arrest in a press release. The suspect is being held at the Larimer County Detention Center, where he faces first-degree murder and felony sexual assault charges. The arrest warrant in the ongoing investigation has been sealed, police said.
It is unclear what type of relationship, if any, Curl may have had with Dick. It is also unclear whether Curl will face additional arson charges tied to the Friday fire at Dick's home.
Authorities identified Dick over the weekend as the young woman whom firefighters found in an upstairs bedroom as they attempted to extinguish a fire that had been set in that room as well as in a second bedroom in the basement of the house.
Firefighters carried Dick from the house, determined that she was dead and returned inside to continue fighting the fire. One cat died in the blaze, while a small dog and another cat were rescued.
The Larimer County Coroner's Office ruled Dick's death a homicide Saturday, finding that she had been sexually assaulted and strangled. Authorities said they believed the pair of fires had been set deliberately.
Missing from the house was Dick's 1997 Nissan Altima, a clue that Davis told ABC News just hours before the Monday arrest would be key to identifying a suspect or suspects in Dick's death.
"We believe that to be a critical piece of the investigation," Davis said. "We believe the person who murdered her is also responsible for taking her car."
It was not immediately clear whether the car ultimately helped lead police to Curl.
Before Monday's arrest, Fort Collins police had been interviewing family, friends and acquaintances, "anyone who had any interaction with her so we could get an idea of who she was, what kind of lifestyle she lived," Davis said, "so we can begin to establish a pattern for her."
Her family was cooperating, as was her roommate, who Davis also identified as Dick's boyfriend. No one had emerged as a primary suspect in the early afternoon when ABC News spoke to police.
Dick's family made a plea Monday outside the home where she grew up for the public to help quickly solve the woman's murder.
"We are confident that the individual or individuals who did this will be brought to justice," Terry Snyder, Dick's uncle and family spokesman said as her father and sister sobbed behind him.
Dick was described by her family as a beautiful, gracious young woman who loved her Chihuahua and was starting to narrow her academic interests as a business student at Front Range Community College.
Andrea Gliva, Dick's sister, said she feared her sister's trusting way may have made her the target of an attacker.
"She would have trusted anyone," a shaken Gliva said. "I think that's maybe part of the reason she's not here today."