LINCOLN, Neb. (AP) — A 58-year-old Nebraska man who had been sentenced to life in prison for killing his ex-wife and his divorce lawyer last November has been found dead in his cell.

Prison officials said Michael Petersen was found shortly after 6 a.m. Monday, and efforts to resuscitate him were unsuccessful. Officials said it appears Petersen committed suicide.

Petersen received his second life sentence last month for the shooting death of Grand Island attorney Todd Elsbernd last Nov. 13. Petersen had already been sentenced to life for killing Nancy Petersen a few hours earlier outside her home in Buffalo County.

Petersen’s attorney had said in court that Petersen remained bitter over money awarded to his ex-wife in their 2005 divorce. Nancy Petersen was awarded half of the couple’s $600,000 estate in the divorce.