JOLIET, Ill. (Reuters) - An Illinois jury on Thursday found former Chicago-area police officer Drew Peterson guilty of murdering his third wife, Kathleen Savio, in a case that received national attention and spawned a popular television movie.

Peterson was convicted of first-degree murder in the death of Savio in 2004 during a contentious divorce, and then staging her death to look like an accident. Savio was found dead in a bathtub, and the death was initially ruled accidental. Suspicions were raised when Peterson's fourth wife, Stacy Peterson, disappeared in 2007.

Peterson was stoic as the verdict was read and he was led from the courtroom in handcuffs.

The conviction followed several requests from the jury to the judge over two days of deliberations. Shortly before the verdict was read, the jury had asked the judge to clarify the meaning of “unanimous.”

Will County Judge Edward Burmila replied that unanimous meant “its common meaning” that all 12 jurors would have to agree on a verdict.

Peterson, a former Chicago-area police sergeant, waged a high-profile public relations campaign asserting his innocence both in the death of Savio and the disappearance of Stacy Peterson, who has never been found and is presumed dead. Drew Peterson is the only suspect in her disappearance.

During closing arguments on Tuesday, the prosecution had asked the jury of seven men and five women to use common sense and consider witness testimony that Peterson threatened Savio, tried to hire a hit man and said he could make her death look like an accident.

The defense argued that he should be acquitted because of the lack of physical evidence of his involvement in her death.

The Peterson case was the inspiration for a popular Lifetime television network movie based on the case, “Untouchable,” starring Rob Lowe.

Peterson will be sentenced on Nov. 26. His first and second wives have remarried.