A 14-year-old boy was arrested Thursday and charged as an adult with first-degree murder in the slaying of a 7-year-old girl, authorities said.

Steven Buelow of Bristol pleaded not guilty at his arraignment in Addison Superior Court and was held on $50,000 bail at the Wood-side Juvenile Detention Center in Essex, authorities said.Buelow was arrested the day after the body of Crystal Sumner was found in a cornfield. Preliminary autopsy results indicated the girl died of suffocation, apparently caused by a gag placed in her mouth, state police said.