ST. PAUL — An Anoka man pleaded guilty to manslaughter Friday in the disappearance of his wife 18 years ago, admitting after years of denial that he strangled her, cut up her body and buried it in a rural area.

As part of Norman Bachman’s plea deal, a charge of second-degree murder will be dismissed. The agreement calls for a prison sentence of 13 1/2 years that will be reduced to 10 years if the body is found based on his information.

Bachman, 53, had long denied involvement in the 1997 disappearance of his wife, Toni Bachman, who was 38 when she was last seen alive at their home in White Bear Lake Township. While police long considered him a suspect, he wasn’t charged until April this year. Authorities would not say at the time what evidence led them to finally charge him, but noted that the pieces had finally come together.

After she vanished, he told police she wanted a divorce. According to the charges, she had become romantically involved online with a West Virginia man. Norman Bachman eventually told the youngest of his three sons that he killed her but that nobody could prove it, the complaint said.

Toni Bachman’s body remains missing, though DNA tests on apparent blood spots in the couple’s basement matched her DNA.

Norman Bachman testified Friday that he cut off his wife’s head, arms, and legs and buried them in separate holes that he dug.

The couple’s middle son told police in 1997 that on April 26, 1977, his father went into Toni Bachman’s room and she screamed.

“He said that the boys all thought the defendant had killed her,” the complaint said. “He said that after Toni disappeared, the house smelled ‘bitter.”’

The middle son also said that some time afterward, his father took the boys to a farm in Verndale in a car that smelled “bitter and awkward.” The car was hauling large coolers, the son said.

The youngest son told police in 2012 that he had worked in a funeral home and came to realize that the smell in the car on that trip was a human corpse.

Dogs searched the Verndale property in 1998 but found nothing.