SARASOTA COUNTY -- Authorities accuse a Tampa Bay-area man of beating his girlfriend to death and attempting to hide the evidence against him by setting a van on fire with her inside.

A murder charge was filed Wednesday, Nov. 1, against suspect Michael Clark, 34, of Brandon, Florida.

The Sarasota County Sheriff's Office began its investigation early in the morning on Oct. 15 when deputies responded to a van on fire on I-75 in Osprey, according to a news release.

Upon putting out the fire, firefighters found 34-year-old Kristen Kelley -- the mother of their three biological children -- dead inside. The probable cause affidavit against Clark notes she was located in an area between the third-row seat and the rear liftgate.

He stayed at the scene; investigators noted Clark had swollen knuckles and blood on his pants, which later was found to be Kelley's blood, the affidavit reads. He told investigators he didn't know how the fire began, how Kelley died nor how he got to Sarasota.

Sheriff's office detectives determined the couple had been seen fighting earlier in the day at a billiards business and both had gotten into the van. Her vehicle was left in the business' parking lot.

Fire investigators reviewed the burned out van and found a gas can inside with a lighter nearby, according to the affidavit.

Clark is in custody without bond, facing charges of murder, arson, tampering with evidence and possession of cocaine -- later found when police took his clothing as part of the investigation.

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