PHILADELPHIA (AP) — A man accused of gunning down an aspiring teacher from Minnesota for his iPod on a Philadelphia street says he didn’t do it and witnesses lied.

The Philadelphia Inquirer reports Marcellus Jones took the stand Tuesday during his trial in the death of Beau Zabel. The 37-year-old is already serving life for killing a witness in the case.

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Jones is charged with the June 2008 murder of 23-year-old Zabel.

Zabel moved from Austin, Minnesota, to Philadelphia to start work in the public schools a few weeks before he was killed during a street robbery.

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Jones also says he was forced to testify Tuesday and wasn’t willing to answer the prosecutor’s questions. The judge told him to comply.

On Monday, Jones repeatedly interrupted proceedings.

Closing arguments are expected later Tuesday.

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