So it went along the route of the Long Island Marathon. Planners are taking no chances with race weekend just days away.
"This is something we shouldn't have to worry about, but unfortunately we do," race director Jason Lipset said.
Hours after the Boston blasts, two Nassau police detectives headed north, not to help investigate, but to gather information in a last minute redesign of security in Eisenhower Park.
This weekend's marathon may only attract just a fraction of Boston's runners, but County Executive Ed Mangano says there's no excuse not to use every available resource.
"We have all these assets. Law enforcement officials have been training for these types of incidents for years, so we're going to deploy them," Mangano said.
For repeat runners, Sunday's race will be very different. All runners, volunteers, and their vehicles will need special credentials just to get close to the starting line.
Spectators will be banned from the starting line. They'll be allowed at the finish, but with no bags.
Along the route, police dogs will check bags and packages for explosives. Some officers will carry radiation detectors.
"People are just trying to have fun and do what they like to do, but with all the stuff that is happening - it's pretty sad what is happening," runner Mario Riola said.
Mangano says the county is spending at least $250,000 on additional security. There was no word on how much security cost last year.