Authorities also released a photo of an expensive watch that was stolen from Reverend Canon Paul Wancura's Shelter Island home back on March 19.
The 87-year-old was badly injured and died this past Monday.
Police hope the reward will help spark tips and lead them to the killer.
Anyone with information in regards to this incident is asked to call the NYPD's Crime Stoppers Hotline at 1-800-577-TIPS (8477) or for Spanish, 1-888-57-PISTA (74782).
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