BROOMFIELD TOWNSHIP, Mich. -- As police frantically worked to figure out how his fiancée's 24-year-old daughter had vanished, a Michigan pastor who had turned to God to shed his violent past went to his flock with a request: pray for her.

But all along, authorities say, he knew the sordid truth about where the young mother was.

The pastor, ex-convict John D. White, later confessed to killing Rebekah Gay to fulfill a fantasy of necrophilia, police said Friday. White drank four or five beers before going to the woman's mobile home and repeatedly striking her head with a mallet and strangling her with a zip tie, according to court documents.

Police said White stripped her dead body but does not remember if he carried out his sexual fantasy. After dumping the body early Wednesday, he returned to Gay's home and dressed her 3-year-old son in his Halloween costume, then later dropped him off with the boy's father.

"He kept saying he's a bad person, he's a pastor, he felt bad for the people in his church. ... I don't recall him being real remorseful at all with regard to the victim or anything else," Isabella County Sheriff Leo Mioduszewski told The Associated Press.

"He just basically said he was attracted to her, thought she was a very cute girl. It's a crazy, tragic situation," the sheriff added.

The case shocked the pastor's roughly 14-member congregation and raised questions about how a man who had found religion after a criminal past could return to that dark history.

White was in jail without bond Friday, a day after he was charged with first-degree murder in Gay's death in a rural area in Isabella County, 85 miles northwest of Lansing. The 55-year-old has asked for a court-appointed attorney.

White was engaged to Gay's mother and regularly watched her young son while she worked, said Donna Houghton, a church elder who had a role in hiring White three years ago to be pastor at Christ Community Fellowship. Church members, she said, were "absolutely floored" by the allegations.

"I protested his innocence until I had the absolute news that he confessed. Then he had no leg to stand on," she told the AP.

Before his arrest Thursday, White called Houghton to ask that she contact other church members and start a prayer chain for Gay, who still was missing at the time.

"He was pretty shook up. He said the police were giving him a hard time," Houghton said.

White confessed that day after being told the woman's body was likely to deteriorate in the cold, wet weather, Mioduszewski said. He said his fantasy had been fueled by pornographic videos.

'Contrite' over criminal past

Houghton said the congregation was aware of White's criminal past when he joined the church. He was released from prison in 2007, after serving nearly 12 years for manslaughter in the death of a 26-year-old woman in Kalamazoo County, according to the Michigan Corrections Department.

He had previously been sentenced to probation for choking and stabbing a 17-year-old Battle Creek girl in 1981.

"He was absolutely contrite," said Houghton, 76. "All kinds of people turn around and meet the Lord and they are a different person. He was doing a lot of good in the community. ... He was doing a lot of good and Satan did not want him doing good and Satan got to him."

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She said White got on her roof and cleaned her neglected gutters last week, a chore that inspired his Sunday talk. She recalled him saying during that sermon that "we need to check closely the seeds we sprout in ourselves. Nothing can be hidden from God."

At the trailer park on Friday, pictures of pumpkins and other Halloween decorations were still on Gay's home. Park resident Matt Brown said White regularly cut through his yard to visit Gay's trailer that was one street away.

Brown, 21, said White seemed to have scratches on his face when he told residents Wednesday that Gay was missing and that her car had been found outside a bar.

"It looked like he was in a struggle," Brown recalled.

Charles Kenworthy, another resident of the park about 11 miles west of Mount Pleasant, said the killing so close was "just scary."

"I would think they'd want to look into different people and their background before they let somebody live here," the 53-year-old said.

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