CAMDEN, N.J. (AP) — Authorities have upgraded charges against a South Jersey man accused of assaulting an acquaintance outside a Jimmy Buffett concert in Camden last week. The victim died of his injuries three days after the assault.

The Camden County Prosecutor’s Office says 21-year-old Matthew Shields of Westville is now charged with aggravated manslaughter.

He is accused of punching 20-year-old Ryan Coyle of Bellmawr before last Tuesday night’s concert at the Susquehanna Bank Center on the shore of the Delaware River.

Authorities say Coyle fell and hit his head on the pavement in the parking lot after being hit from behind. He died Friday night at Cooper Hospital in Camden.

Shields was initially charged with aggravated assault. His arraignment was set for Tuesday afternoon.

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