Perth Amboy police say they saw 44-year-old Miguel Rosario buy two bags of cocaine from another man in the area of High Street and Hall Avenue.
Rosario is a senior corrections officer at the Edna Mahan Correctional Facility for Women in Clinton.
The guard is charged with possession of cocaine and conspiracy.
The Home News Tribune of East Brunswick reports members of the Perth Amboy Police Department's Special Investigation Bureau seized about $8,500 worth of cocaine after arresting the man accused of selling the drug.
Information from: Home News Tribune, http://www.mycentraljersey.com