BEDFORD, VA., JUNE 18 -- Jens Soering, testifying today in his murder trial, denied slaying Nancy and Derek Haysom and said his ex-girlfriend, the Haysoms' daughter, killed them out of hate while on drugs.

Soering's testimony was a nearly complete reversal from his own statements to police four years ago and from the story Elizabeth Haysom, his ex-girlfriend, told the Bedford County Circuit Court jury last week.

Soering, 23, testifying quietly and confidently, told jurors he never helped plan the Haysoms' March 1985 deaths, as both defendants had claimed in the past, nor was he aware that Elizabeth Haysom left their weekend retreat in Washington, D.C., to kill her parents in their Bedford County home.

Nonetheless, Soering said, he agreed out of love for his former girlfriend to take responsibility for the killings because he was afraid she would face the death penalty, while he thought he would only be deported and receive a light sentence because he is the son of a West German diplomat.

"I loved Elizabeth, and I believed the only way I could save her life from the electric chair was to take the blame," Soering said. "I agreed to sacrifice five years of my life to save her life."

Elizabeth Haysom, 23, the prosecution's key witness at Soering's trial, was convicted in 1987 of being an accessory to the killings and is serving a 90-year prison sentence.

Commonwealth's Attorney Jim Updike attacked Soering's story, accusing him of making up a tale while spending four years in a London prison fighting extradition to the United States.

"You began developing plans . . . based on different lies," Updike said.

"No," Soering answered.

According to Haysom's testimony last week and two statements Soering made four years ago, they plotted the slayings while visiting Washington, and Soering drove to Boonsboro, Va., and killed the couple while Haysom stayed in Washington to establish an alibi.

Soering testified today that after the killings Haysom sat on the edge of a hotel bed and started talking. She "basically kept repeating the same things over and over again, 'I killed my parents. I killed my parents,' " Soering testified. "That it wasn't her that did it, it was the drugs that made her do it. She said that a lot . . . and that her parents deserved it anyway."

Soering said Haysom begged him to help her by taking the blame.