An autopsy report has confirmed Monkees singer Davy Jones died of a heart attack.

The report, released Thursday, notes that Jones had severe plaque buildup in his arteries, according to TMZ.com .

The report also states that evidence of cannabinoids, a class of drugs that includes marijuana, was found in his system. The cannabinoids were not a factor in Jones' death.

Jones died February 29 in Florida at the age of 66.

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