EAST MEADOW - Nassau County Executive Ed Mangano today announced stepped up security measures for the Long Island Marathon in the wake of the Boston bombings.

Radiation detectors, extra police and K-9s will be on hand for the marathon, which is set for Sunday. All runners and volunteers must pick up their credentials ahead of time.

Bags and backpacks will be prohibited near the finish line, Mangano says. Attendees must put items in a clear plastic bag provided by race organizers.

One of the biggest changes will be that spectators will not be allowed at the starting line.

Mangano says all the extra safety measures, including police overtime, could cost $250,000 or more.

For Mangano's entire news conference, watch the clip to the left or click News 12 Extra on Optimum TV channel 612.