A Hillsborough County man is behind bars after investigators say he killed the mother of his kids and then burned his van with her body inside.

The horrific details are outlined in a report from authorities. 34-year-old Michael Clark is accused of murdering Kristen Kelley, his longtime girlfriend and the mother of three of his children.

Surveillance cameras reportedly recorded video on Oct. 15 of the couple arguing outside of her workplace. Over the course of about an hour, investigators said, the video shows Clark got physical, putting Kelley in a headlock before the two got in his van and drove off.

Authorities maintain that sometime after that altercation, Clark beat Kelley to death. He then reportedly put her body in his van, drove south on I-75 to Sarasota and pulled over on the side of the road.

Investigators said they found the van Clark was driving engulfed in flames with Kelley’s body inside and Clark standing outside.

When questioned, investigators said Clark told them he didn’t know how Kelley died, how the fire started or how he got to Sarasota. But reports show he had the victim’s blood on his clothes, bruises on his hands along with a gas can in the van and a lighter nearby.

Authorities report Clark was taken to the hospital and subsequently released, but then arrested Thursday and charged with Kelley’s murder, arson, tampering with evidence and possession of cocaine.

According to county records, Clark was arrested days before the incident for aggravated assault. In that incident, he reportedly put a knife to his Kelley’s throat and threated to kill her and himself.

Friends of Kelley said the news of her death is devastating. They describe her as a caring, hard-working mother who would do anything for her children.  

“Kristen was definitely a vibrant person. Always happy, always uplifting, always wanting to go the extra mile, always wanting to have fun, super fantastic mother,” Kelley’s friend and co-worker Paige Calhoun said. "It’s devastating. It’s devastating. On her first night here during our grand opening she showed me a video of all of the kids in the car all saying 'Go mommy, go mommy, go! You’re gonna do great, Mommy.' Everything was geared towards those children, everything.”

Calhoun said she’s not focusing on the horrific details of her murder. Her goal is to help Kelley’s children and Kelley’s parents. She's started a Gofundme account to help the family going forward, and has already raised more than $11,000 via a benefit event for the family.

"We did a silent auction, a 50/50 raffle. We did a regular raffle," Calhoun said. "We had entertainment donated, all kinds of items donated. It was incredible to watch the community come together for [Kelley]."

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