A 30-year-old man was shot dead in a hail of bullets during an argument at a Brooklyn pier Sunday morning, police said. John Garvin was blasted in the head and body multiple times when a dispute exploded into violence near the Belt Parkway and Rockaway Parkway at the Canarsie Pier around 3:14 a.m., police said. The deadly shooting occurred at Canarsie Pier. Detectives comb Canarsie Pier for evidence after John Garvin, 30, was fatally shot. Kyle Mazza/ShutterstockHis grief-stricken family wept and embraced at the blood-soaked crime scene hours after the senseless shooting, the Daily News reported.