By David Madden

MOUNT HOLLY, Nj. (CBS) — Authorities in Burlington County, New Jersey say charges were upgraded on Wednesday against a 52-year-old Hainesport man who allegedly struck a teenager with his car and fled the scene of the collision.

16-year-old Shawn Hall was killed on May 25 as he walked along the Mount Holly Bypass, near Rancocas Road.

The driver, Kevin Voorhees, is now charged with death by auto in addition to the original charges of drug possession and leaving the scene of an accident.

The county prosecutor indicates that toxicology tests indicate Voorhees had alcohol, marijuana and cocaine in his system at the time of his arrest.

Voorhees is free on $150,000 bail.