2 men arrested after fatal overdose prompts monthslong investigation

Two men were arrested on cocaine trafficking charges after a months-long investigation into a fatal overdose, prosecutors said.

William Sarney, 62, of Nantucket, and Andre Sylvia, 56, of Wareham, were arrested as a result of this investigation, the Cape and Islands District Attorney’s Office said in a statement. They were detained on Thursday on charges of “engagement in illegal drug activity.”

Sarney and Sylvia were both charged in Barnstable District Court with felony conspiracy to violate the drug law and trafficking 200 grams or more of cocaine, according to court records. Sylvia is also currently facing similar drug distribution charges in Wareham District Court.

Sarney pleaded not guilty at his arraignment Friday and was being held without bail pending a dangerousness hearing scheduled for Tuesday, court records show. Sylvia has not yet been brought to trial.

The investigation began in November 2025 when Massachusetts State Police investigators responded to a fatal overdose in Barnstable County, according to prosecutors. The Office of the Chief Medical Examiner determined the cause of death to be diabetic ketoacidosis, which is caused by severe insulin deficiency, exacerbated by cocaine intoxication.

Investigators later determined Sylvia was the main supplier of cocaine, the district attorney’s office said. Sarney was also linked to Sylvia through a Barnstable police investigation, according to officials.

On Jan. 8, Barnstable police arrested Edward Gillespie, 62, of Nantucket, who was allegedly preparing to transport a kilogram of cocaine from Hyannis to Nantucket, according to the district attorney’s office. Gillespie was identified as a drug supplier, and a subsequent search of his home turned up more cocaine, amphetamines, evidence of drug trafficking and about $10,000, according to officials.

Prosecutors said Gillespie was charged in Barnstable District Court with trafficking more than 200 grams of cocaine. He was arraigned on January 9 and is scheduled to appear in court on March 25 for a hearing.

The following months of investigation led to broader cooperation between local and state police investigators, according to prosecutors. Local departments in Barnstable, Nantucket, Sandwich and Wareham, state departments from the Cape and Islands, Plymouth County, the Cape Cod DEA Task Force and State Police all participated.

Law enforcement executed search warrants on March 12 at properties on Nantucket and Wareham, leading to the arrests of Sarney and Sylvia, the district attorney’s office said. Both were being held without bail.

Attorney information for Sarney and Sylvia was not immediately available Sunday morning.