WILMINGTON -- A 57-year-old Billerica man is dead after a crash in Wilmington on Friday morning, but police are still investigating whether a medical condition or the crash was the cause of death.

Gary Roy, 57, of Billerica, died at Lahey Clinic in Burlington on Friday after he was involved in a single-vehicle crash on Chestnut Street, near Apple Tree Lane, in Wilmington, according to police and Roy's obituary.

Deputy Chief Robert Richter said the cause of the crash remains under investigation, and that police are trying to determine whether Roy was suffering from a medical condition that caused both the crash and his death.

That investigation is ongoing.

Roy leaves behind six children and other family. One of his greatest joys was spending time with his family, according to his obituary.

Roy formerly worked at his family's business, Roy Brothers Trucking, in Billerica.

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