Two Brooklyn bicyclists were killed in separate incidents within two hours early Thursday morning.In the first case, a man was struck and killed by a gasoline-delivery truck on Union Avenue in Williamsburg. The truck was turning onto Ten Eyck Street shortly after 4 a.m. when it hit the cyclist, who police said was trying to pass the truck and had been riding on the wrong side of the street. No charges were filed again the driver.About two hours later, another man was riding his bicycle in Bedford-Stuyvesant and was hit by a white van at the intersection of Utica Avenue and Fulton Street. Police determined the driver of the van, Alfred Taylor, 41, of Brooklyn, had been speeding. He was arrested and charged with criminally negligent homicide.Police were withholding the names of cyclists pending notification of family."We are stunned and outraged to learn that two cyclists were killed within the span of hours," said Paul Steely White, executive director of Transportation Alternatives. "Protected street space for cyclists is the surest way to make biking safe. The city must continue to work tirelessly to provide bicyclists with the protections necessary to ensure safe travel."