(STMW) — A man charged with strangling and robbing an 88-year-old World War II veteran hanged himself in his cell Thursday afternoon at the Cook County Jail, an autopsy found.

Matthew Stoecklein, 58, was pronounced dead at the jail at 2600 S. California Ave. at 1:55 p.m., according to the Cook County Medical Examiner’s office.

He was found hanged in his cell, the Cook County Sheriff’s office said.

An autopsy conducted Friday found that Stoecklein died from hanging and ruled his death a suicide, the medical examiner’s office said.

Stoecklein was charged with killing his neighbor, Purple Heart medal recipient John Poyer, in Poyer’s apartment in the 500 block of Hiawatha Drive in Elgin on Nov. 21, authorities said.

About 8 p.m. on Nov. 21, Stoecklein knocked on Poyer’s apartment door, and was let in once he identified himself, according to Cook County Assistant State’s Attorney Jason Coelho.

Sometime after Stoecklein entered, Poyer was heard screaming before Stoecklein strangled him and took $300 from the apartment, Coelho said.

An acquaintance of Stoecklein’s approached police and said he would wear a wire to speak with Stoecklein about Poyer’s death. On tape, Stoecklein told the acquaintance he had strangled Poyer for 10 minutes before he died, an effort that left him very tired, prosecutors said.

Stoecklein, who has a previous felony drug conviction, lived in a second-floor apartment in the same building as Poyer, authorities said.

Poyer was found dead at his home about 6:15 p.m. the following day by family members who hadn’t heard from him in several days and went to check on him, police said.

 (Source: Sun-Times Media Wire © Chicago Sun-Times 2013. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)

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