SAN DIEGO -- A man serving a 70-year prison term for rape pleaded innocent Friday to murder charges for the 1993 killings of two young boys in the Palm City area of south San Diego.

Video

Hear From Erskin's Attorney, Victim's Mother

Scott Erskine (pictured, left), 38, was implicated through advanced DNA testing last March in the deaths of 13-year-old Charlie Keever and 9-year-old Jonathan Sellers.

The boys disappeared while riding their bikes following a weekend lunch at a fast-food restaurant on March 27, 1993.

Erskine answered "not guilty" Friday when Superior Court Judge Peter Deddeh asked him how he wanted to plead to the two counts of murder.

The defendant said "Yes, sir" when the judge asked if he denied the special circumstance allegations.

His attorney, Larry Ainbinder, said that his client was in shock and asked the community to reserve judgment.

"Slow down. Let's just wait here. Let's see what happens," Ainbinder told reporters. "We don't want to compound the tragedy of two boys deaths with a mistake made as we rush to judgment."

The mothers of both victims were in court but reportedly had little to say, as Erskine denied the charges, which include special circumstance allegations of torture, sexual assault and multiple murders.

"I just want to thank the media for everything they have done and for keeping Charlie's name alive. And I hope justice is done," Maria Keever said.

Milena Sellers was hurried from the courtroom and did not speak to reporters.

District Attorney Paul Pfingst said that he decided to charge Erskine after additional testing of DNA material from the crime scene came back to his office last Friday.

The bodies of the boys turned up on the banks of the Otay River two days after they were reported missing in an open, brushy area near the end of Saturn Boulevard.

Erskine, who lived in the South Bay at the time of the killings, was linked to the crimes by re-analysis of biological material he allegedly left on one of the boys' bodies during a sexual assault.

The defendant was identified as a possible suspect in the crimes through a new statewide DNA database used to check inmates in the state prison system, Pfingst said.

The probability of a person randomly matching the perpetrator's DNA profile is about 1 in 600 billion, according to authorities.

Erskine -- who is already doing time for raping a woman in San Diego seven months after the boys' killings -- was ordered held without bail.

A decision on whether he could face the death penalty, if convicted, will be made after a Dec. 4 preliminary hearing.