BOISE -- A Boise teenager is facing felony charges in connection to the death of a man found wrapped in a tarp and bound to a playground slide in the Foothills in August.

Anthony Barclay, 19, was originally charged with burglary and grand theft after police say he was caught trying to pawn a rifle belonging to the victim, 61-year-old Mark Irwin of Boise. Felony counts of failure to notify of death and destruction of evidence were added Tuesday.

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Francis March, 45, is charged with first-degree murder in Irwin's death. Prosecutors say she drugged the victim and suffocated him with a plastic bag before hog-tying his body to the slide and dumping his corpse just on the other side of the Boise County line.

Authorities say March had planned to return to the foothills to better dispose of Irwin's body, but his remains were discovered by police Aug. 26, several weeks after he was reported missing.

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A motive in the murder remains unclear, but prosecutors say Irwin was not targeted at random.

Police say the investigation is ongoing, and more charges may be filed in the case. Both Barclay and March are due to appear in court later this month.