An Arkansas man who already is serving a lengthy prison term will spend the rest of his life in prison for the death of an elderly Washington County woman who was terrorized by robbers posing as gas company workers.

Washington County President Judge Debbie O'Dell Seneca today sentenced Mark M. Fisher to life without parole following his conviction for second-degree murder in the death of Freda Dale, 89, of Peters, on Jan. 29, 2003.

She also sentenced Mr. Fisher to serve an additional 12 to 24 years for his conviction for aggravated assault, robbery, burglary and conspiracy in the attack on Mrs. Dale and her husband, Shannon.

The Washington County sentence is to follow a 70-year term Mr. Fisher is serving now in Arkansas, where he was convicted of robbery, theft and burglary in a series of break-ins.

A Washington County jury in September convicted Mr. Fisher, concluding he was one of four people who posed as gas company workers, entered the Dales' house and bound the couple with duct tape before assaulting Mrs. Dale's 90-year-old husband. The other three assailants remain unidentified.

Prosecutors relied on fingerprints and DNA evidence to convict Mr. Fisher.

State police said they found his DNA on a cigarette butt outside the Dales' home. Experts also testified that DNA found on duct tape used to bind Mrs. Dale could have come from Mr. Fisher.

Police also found a fingerprint on an envelope in the house that matched Mr. Fisher's right thumb.

Terrified by the intruders, Mrs. Dale died of a heart attack after they beat her husband. Mr. Dale survived the attack but died in February at 95.

Mr. Fisher's family, from Texarkana, Ark., insisted through his trial that he had been in Arkansas on the day of the robbery. They also contended that he'd done paving work on the Dales' driveway before the murder, accounting for his DNA and fingerprints at the home.

But Mr. Fisher's attorney, public defender Glenn Alterio, called no witnesses to establish that Mark Fisher worked for the Dales.

His most notorious case in Arkansas was similar to the crimes against the Dales. Mr. Fisher and an accomplice barged into the home of an 88-year-old man, threw him to the floor and stole the $1,060 he was carrying.

Nearly four years after the attack, in the fall of 2006, Mr. Fisher was charged with homicide and burglary after being linked by DNA found at the scene.

According to testimony yesterday, a man posing as a gas company worker struck up a conversation with Mr. Dale in his driveway that day. When they walked inside, Mr. Dale later told investigators, three more men were in his kitchen clutching Mrs. Dale.

After binding the couple's wrists and legs with duct tape, the robbers scoured the house for money. Finding none, they returned to Mr. Dale, punched him in the face and kicked him in the ribs, all the time asking him where the money was. Mr. Dale told them he didn't have any, but they continued to beat him, twisting his middle finger as a means of torture.

He was serving 70 years in an Arkansas jail for various robberies and burglaries before being charged with the crime in Peters.