The Suffolk County Grand Jury yesterday returned a three-count indictment charging a Level III sex offender with the rape and murder of a 48-year-old mother earlier this year, Suffolk County District Attorney Daniel F. Conley said today.

FITZHUGH NEWTON III (D.O.B. 3/26/59) of Roxbury was indicted for two counts of aggravated rape and one count of first-degree murder for the homicide of Jewell Allsop. Allsop was most recently living in Arlington but died in Dorchester; her remains were discovered early on Feb. 26 in the rear of a delivery truck on Columbia Road.

“Whatever satisfaction there is in identifying Ms. Allsop’s alleged killer is far outweighed by knowing the horror of her final moments,” Conley said. “We can only hope that this step in the process reminds her loved ones that we will not rest until justice has been done.”

Newton is expected to face arraignment tomorrow in Suffolk Superior Court.

Workers at a Dorchester food preparation and delivery service notified Boston Police when they observed the rear door to one of their trucks open and found Allsop unresponsive inside. Emergency medical technicians pronounced her dead at the scene.

An autopsy performed by the Office of the Chief Medical Examiner deemed her death a homicide by strangulation. Pathologists also found abrasions on her face; blunt impact trauma to her head, neck, and torso; and evidence that she had been raped.

Biological evidence recovered from the crime scene and from the victim’s remains was processed by Boston Police criminalists, who developed from them a DNA profile believed to be the attacker’s. That profile was then submitted to the FBI’s Combined DNA Index System – or CODIS – a database containing millions of DNA samples from offenders both known and unknown.

The DNA sample from Allsop’s murder came back as a “hit,” matching a sample that Newton had previously submitted to CODIS. Under Massachusetts law, anyone convicted of a felony must provide such a sample; Newton has felony convictions dating back to 1979, when he was found guilty of kidnapping and assault with intent to rape.

“The CODIS database has been a boon to police and prosecutors,” Conley said. “We’ve used it to build cases in rapes, murders, and other violent crimes that otherwise might never have been solved.”

Under Conley’s leadership, Suffolk prosecutors have also used CODIS to exonerate a man wrongly convicted of rape and indict the alleged true culprit. Anthony Powell was freed several years ago after serving more than a decade in prison for a 1991 rape after police and prosecutors undertook an initiative to re-examine unsolved sexual assaults with newly-admissible DNA evidence. Prosecutors then indicted the DNA profile of the then-unknown perpetrator before the statute of limitations expired.

Last summer, prosecutors said the perpetrator had been identified as JERRY DIXON (D.O.B. 4/19/73) after Dixon was obliged to submit a DNA sample to CODIS on an unrelated offense. He is being held on $1 million cash bail.

Newton remains held without bail following his July 8 arraignment in Roxbury District Court. He is expected to appear in the Magistrate’s Session of Suffolk Superior Court tomorrow morning with attorney Matthew Kamholtz.