ANCHORAGE, Alaska (AP/CBS St. Louis) — A 24-year-old airman accused of killing a fellow airman from Missouri had a blood-stained claw hammer in his pickup, and prosecutors said his cellphone history recorded visits to websites showing how to dispose of a human body.

James Thomas pleaded not guilty during an arraignment Tuesday in Anchorage Superior Court, the Anchorage Daily News reported. He’s charged with first-degree murder, three counts of second-degree murder, robbery and six counts of evidence tampering in the death of Clinton Reeves, 22, of Raytown, Mo.

Reeves failed to report for work at Joint Base Elmendorf-Richardson in Anchorage on April 23. His rental car was found later, with uniforms and groceries inside. His body was found May 8 in a ravine in suburban Anchorage.

An autopsy determined he died of blunt force strikes to the head.

Thomas earlier was arrested for evidence tampering. A grand jury indicted him Friday on the more serious charges.

Reeves had recently received about $4,000 in an insurance settlement after a car accident, and he was shopping for a new vehicle. Reeves’ mother, Judy Davis, has said she believes that money was the basis for his murder.

According to court documents, Thomas and Reeves has spent time together looking at used vehicles, KTUU reported.

“James told me that,” Davis told the Anchorage Daily News. “I was texting him the day I was looking for my son. I pu8lled up one of the numbers on my son’s phone, and I just happened to get James,” she added.

Authorities say Thomas changed his story repeatedly about his involvement with Reeves.

He previously told Anchorage police his missing friend texted him a few days after he vanished, saying he was sick and getting medical treatment.

Before his arrest on evidence tampering charges, Thomas contacted Air Force authorities and said he found Reeves at Thomas’ home on April 19. Thomas said Reeves was lying on a loveseat with a towel over his head near an unknown man holding a gun.

Thomas said the man held him at gunpoint, had him turn around, and ordered him not to move. Thomas said the gunman left with Reeves.

Court documents allege Thomas cleaned blood off furniture and a carpet and disposed of cleaning rags, towels, paper towels and the loveseat.

“The physical evidence belies Mr. Thomas’ stories to law enforcement,” prosecutors say in court documents released Tuesday. “In Thomas’ Nissan pickup, detectives located a claw-type hammer. The Alaska State Crime Lab determined the hammer’s head and claw to be stained with human blood. The State Crime Lab is processing the hammer in an effort to determine if the blood belongs to Reeves.”

Prosecutors also say Thomas borrowed a co-worker’s phone, and forensics evidence shows he had driven to the area where the body was found.

“Detectives also analyzed Thomas’ cellphone,” the documents say. “Forensic analyses of the cellphone show that Thomas visited various websites that reference how to dispose of a human body shortly after Reeves disappeared.”

Thomas is being held on $100,000 bail.

He appeared in court Tuesday for arraignment for the murder and burglary charges, and pleaded not guilty.

(TM and © Copyright 2012 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2012 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)