Newtown (AP) - A 68-year-old man pleaded not guilty Tuesday to killing his wife, whose skeletal remains were discovered under a barn floor a quarter-century after she vanished from their home.

John Heath has said his wife, Elizabeth, disappeared in 1984 and he didn't know where she went. A contractor working on a converted barn on the Heaths' former property in Newtown found her remains in 2010. The medical examiner's office ruled she died from blows to the head.

Heath, of Bridgewater, was arrested Monday on a murder charge and was being held on $1 million bond.

Messages left Tuesday with the public defender's office, which represented him in court during his arraignment, weren't immediately returned.

Elizabeth Heath was in her 30s when her husband reported her missing, a little over a week after he filed for divorce. The couple had a 4-year-old daughter.

Heath remarried the following year, to a woman who baby-sat their daughter, according to his arrest affidavit.

Elizabeth Heath's sister-in-law said she had told her while crying after an argument that her husband was going to kill her and that if anything happened to her, "you know that John did it," according to the affidavit.

Heath told police that $600 was missing from their dresser drawer after his wife disappeared. But authorities said he told others that she took no money.

The woman's left forearm was broken, suggesting an assault, according to the medical examiner.

When a detective told Heath about his wife's injury and that the bone was smashed, Heath replied, "Smashed like a ...," not finishing his sentence as he raised his arms upward as if he was holding something and moved his arms downward, according to the affidavit.

The woman also had multiple fractures on her skull. Two broken arm bones were consistent with defensive wounds, the affidavit said.

A woman who introduced the couple in the 1970s said John Heath was a Vietnam veteran traumatized by his war experiences, according to the affidavit.

A marital therapist is quoted in the affidavit as saying he expressed rage at his wife.

"What stands out in recollection of our sessions is/was the volatility and rage expressed by Mr. Heath towards Elizabeth," the therapist told authorities.

The News-Times of Danbury reported that Heath was wearing oxygen tubes during his arraignment in Danbury Superior Court. Prosecutors said at the arraignment that officials acted quickly to arrest Heath after a moving truck was seen at his home over the weekend.