INDEPENDENCE (Missouri) - A SUBURBAN Kansas City woman pleaded guilty on Monday to killing a woman whose sexual torture and suffocation were videotaped.

In a deal with prosecutors that allowed her to avoid the death penalty, Dena Riley, 42, pleaded guilty to first-degree murder in the May 2006 death of Marsha Spicer, who was suffocated during sex at an Independence apartment that Riley shared with her boyfriend.

In addition to the murder of Ms Spicer, 41, of Independence, Riley also pleaded guilty to the kidnapping and assault of Ms Michelle Huff-Ricci, 36, of Kansas City.

Ms Huff-Ricci's remains were found in nearby Clay County, where Riley and her boyfriend, Richard Davis, are charged with capital murder.

Riley sobbed throughout the hearing as she answered each question from the judge, prosecutor and defence attorney with a simple 'yes' or 'no'.

As part of the deal, Riley was sentenced to life without parole for the murder charge and to eight additional life sentences and 239 years in prison for 25 other counts.

Earlier this year, Davis was convicted and sentenced to death for Ms Spicer's slaying. He also is charged in the federal case.

During Davis' week-long trial in July, the key evidence was videotapes that prosecutors say Davis and Riley made to fulfill Davis' violent sexual fantasies.

Riley also agreed to plead guilty in Kansas on a federal charge of kidnapping a 5-year-old girl related to Davis after fleeing the Kansas City area in May 2006.

Court documents said the girl had injuries consistent with sexual abuse.

Jurors watched graphic DVD recordings taken from those tapes, one of which showed Ms Spicer's death. -- AP