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Missing mom's diary sheds light on why husband was arrested

Updated at 6:35 p.m. ET: The husband of a Missouri woman who has been missing for nearly a year was charged with first-degree murder Monday even though his estranged wife's body has not been found.

In a probable cause affidavit released Monday, law enforcement officials outlined why they believe Clay Waller, 41, lured his soon-to-be-ex wife to his home to kill her.

Officials also noted that they discovered Jacque Waller’s diary in her laptop, which was found close to where her Honda Pilot had been parked off a highway. In it, she wrote that Clay Waller, a former police officer, had repeatedly threatened to kill her if she left him. She wrote, “He told me that a divorce would be my death sentence.”

Read the probable cause affidavit 

Clay Waller was sentenced to five years in federal prison for threatening his wife’s sister in an online posting. Jacque Waller's sister is currently caring for the Wallers’ 5-year-old triplets.

"There is a bit of relief in knowing that charges have been brought against Clay Waller," Jacque Waller's father, Stan Rawson, said in a statement. "The case is now in the hands of the prosecuting attorney, and we are confident that we will now finally get justice for our girl."

The Wallers had been having marital trouble and were on the verge of divorce last June, Rawson told The Associated Press last year.

Jacque Waller and her triplets had moved into her sister’s home, and she had started seeing another man. Clay Waller, too, had a new partner.

On June 1, Jacque and Clay Waller met with their attorney. Jacque had agreed to let Maddox, one of the triplets, spend the day with his father. She called her sister to say she would return home immediately after picking up her son.

She never came home. Clay Waller’s girlfriend said Clay had asked her to take care of the boy for the night – the first time she had ever spent time alone with Maddox.

A neighbor said that on that day she saw Jacque Waller’s Honda Pilot in Clay Waller's driveway next to his red truck. His truck was hooked up to his boat, which he then drove away. Jacque was nowhere to be seen. That evening at 9:45 p.m., another neighbor,  approached Clay Waller on his patio and said he had heard Jacque was missing. Waller, out of breath, said he'd just been on a bike ride.

Later, Jacque Waller's Honda Pilot was found on Interstate 55 with a flat tire. Police said the tire had been punctured after it had stopped running.

Clay Waller initially told police that they had been together because Jacque had come over for sex, that they had argued and she left on foot. Later, he told police that Jacque had a nose bleed when his head hit her nose, and that she had bled a lot.

More than 100 volunteers were searching again today for Jacque Waller, a 39-year-old mother of triplets missing for six weeks from her Missouri home. TODAY's Lester Holt speaks with Waller's parents about their fears and suspicions.

When police searched Clay Waller’s home, they found blood stains on the walls that had apparently been washed down. They also found green carpet from the hallway cut up in squares and stored beneath house. DNA analysis of blood stains on the carpet indicated that the blood matched Jacque Waller’s.

For hiding the carpet, Waller is also charged with tampering with evidence.

The FBI said last year that Clay Waller suggested to his father that he had broken Jacque Waller's neck and buried her in a hole that he dug in advance. But Clay Waller has not made any confession to police, and his father died before he could testify.

Waller was sentenced to five years in federal prison in December and is serving time at a prison in the state of Louisiana. He pleaded guilty in October to threatening Brennecke through an online posting.

Following the charges, Clay Waller’s attorney released a statement: “Clay misses his wife and he hopes she is found alive. He sincerely sympathizes with the Rawson family. His heart goes out to them. However Clay had nothing to do with his wife’s disappearance, and we have substantial evidence to support that claim.”

Cape Girardeau County prosecutor Morley Swingle said one of the tampering charges alleges Clay Waller concealed his wife's body. The second alleges he "concealed bloodstained carpet from the hallway of his home" in Jackson, Mo., about 100 miles south of St. Louis.

Swingle said Missouri lets prosecutors seek the death penalty if at least one of 17 "aggravating factors" can be proven. He said none of the aggravating factors are involved in the Waller case.

The Associated Press contributed to this report.

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