Authorities say a suburban Saint Louis teenager facing trial on a first-degree murder charge has been found dead in an Illinois jail cell. The Belleville News-Democrat reports that authorities found 19-year old Damon Stidimire hanging from a sheet Thursday night at the Saint Clair County Jail.  Sheriff Rick Watson could not say when Stidimire was last seen alive.  Standard procedure calls for cell checks every 30 minutes.  Stidimire was being held in lieu of $500,000 bail in connection with the stabbing death of a man whose brother Stidimire had been seen arguing with last Saturday.  The victim, 25-year old Brianzellous T. Allen, died last Monday at Saint Louis University Hospital.