AP file photo Under a deal that a judge must approve, Hans Reiser led police to his wife's body in exchange for the chance of a lighter sentence.

OAKLAND — A long-running murder mystery was nearly solved Tuesday as investigators confirmed that the body revealed to them by convicted murderer Hans Reiser is that of his estranged wife.

The prominent software engineer was found guilty of first-degree murder in the case in April even though Nina Reiser's body had not been found. Reiser showed police the body in exchange for a chance of a lighter sentence, said prosecutor Paul Hora.

The deal, which must still be approved by a judge, was made with the support of Nina Reiser's family. "Ultimately this was done for the family," Hora said.

Police said Nina Reiser's identity was confirmed by dental records, jewelry and clothing. They said the cause of death is still under investigation and declined to give many specifics of what they found when Reiser led them to the body Monday.

But Oakland police Lt. Ersie Joyner III did say evidence from the grave, which was in a ravine in a park not far from Reiser's house in the Oakland hills, indicates Reiser did not have help from anyone else.

The disappearance of Nina Reiser, who was last seen on Labor Day weekend in 2006 when she dropped off the couple's two children for a visit with their father, had prompted a long and intense search, including the area where the body was found.

But Joyner said the grave was in a remote area at least 40 yards from any path and probably would never have been found without Reiser's directions.

At trial, the 44-year-old Reiser had adamantly denied he had anything to do with Nina Reiser's disappearance, and the defense suggested she might have run away to her native Russia.

Prosecutors said that was nonsense, pointing out that traces of her blood were found in his home and car. Witnesses testified that she would never have left her children.

Reiser took the stand for several days, giving long, rambling answers and at times getting scolded by the judge for arguing with the prosecutor.

After jurors convicted Reiser, the defense approached prosecutors with an offer, Hora said.

If a judge approves, Reiser will be allowed to plead guilty to second-degree murder in return for showing authorities the body and giving up his right to appeal, Hora said.

Reiser's defense attorneys did not immediately return messages Tuesday. On Monday, his attorneys declined to comment on whether Reiser had been offered a deal.