Mark Hacking "just snapped" and killed his pregnant wife after she learned he had lied for years about his education and career plans, his father said Thursday.

"I think it's clear that this whole house of cards he had built, all this deception, had come to an end. He had been found out. His wife discovered his deception and confronted him with it, and I just think he just saw his whole world collapsing and broke down," Douglas Hacking said.

"He just snapped and did something there's no explanation for," he said.

Hacking said he based his belief in part on reports that Lori Hacking, 27, left work stunned and sobbing on July 16, three days before her husband, a 28-year-old hospital orderly, reported her missing. Colleagues at the brokerage firm where she worked said they believe an administrator at a North Carolina medical school had called her back to say Mark Hacking was not enrolled there.

Douglas Hacking said Mark told his brothers Scott and Lance on July 24 at a psychiatric ward that he had killed his wife in bed while she slept and threw her body in a trash bin.

Both Scott and his father are physicians, and Lance Hacking is an electronics engineer. Douglas Hacking said he believed Mark probably felt pressured by his family's achievements.

On Thursday, a judge extended to Monday the deadline for District Attorney David E. Yocom to file charges in the case.