The bombs were hidden in a garbage can just past the half-mile mark of Saturday's 5K race in Seaside Park, N.J., where more than 2,000 runners and spectators had gathered to raise money for wounded Marines.
The distance to the trash can was five minutes for most runners. The explosion had the potential to injure, even kill, those closest to it.
But the event attracted more runners than expected. So race director Frank Costello pushed the 9:30 a.m. start time back a half-hour _ a decision that he said prevented a "disaster."
One of three pipe bombs in the garbage can exploded at 9:35. The two others, for reasons unknown, did not. Some runners and organizers didn't hear the boom over the blare of speakers near the starting line.
Then came police on bullhorns. Get away from the boardwalk, they ordered. The crowds stepped back reluctantly, some thinking it was a temporary delay.
"At first, I don't think people realized the seriousness of it," said Christopher Raimann, 45, a race volunteer who also works at the Ocean County Sheriff's Department.
Then word spread. A bomb had gone off in Seaside Park, a tiny Shore borough of 1,500 that calls itself "the Family Resort," not a place someone would expect to be a terrorist target.
But that's exactly what authorities said it was Monday as they captured Ahmad Khan Rahami, who they said was responsible for the Seaside Park incident and a bombing in Manhattan, also Saturday, that injured 29 people.
"That would have been a disaster if that race had started on time," Costello said of the Semper Five Marine Corps Charity 5K.
"We definitely would have had casualties," said Toms River Mayor Thomas F. Kelaher, a retired Marine and one of the race sponsors. He was standing on a stage announcing runners' names when police stopped the event. He said he never heard the explosion.
On Monday, the blast site on Ocean Avenue, an area of two-story homes and sandy beaches, was free of police tape and flashing lights as heavy rain fell. Some residents still felt shaken.
"This is a little town, and you don't expect anything like that. You feel safe, and it's no longer safe," said Faye Haring, 70, a retired Postal Service carrier who lives five blocks from where the bomb went off.
Toni Silvestri, 50, heard the explosion while working at Nino's Pizza, about six blocks away.
"I didn't think much of it," he said. "I mean, what happens around here? Nothing. Nothing ever happens around here."
Before the explosion, an unattended backpack not far from the finish line also caused confusion Saturday. Kelaher asked twice from the stage for its owner to claim the backpack after a woman found it and told race officials.
When, a few minutes later, Kelaher heard police loudspeakers telling people to leave, he suspected the backpack _ which turned out to be unrelated to the bombing _ was the cause.
"I thought, 'Jesus, are we overreacting?' " he said.
The explosion happened just as a one-mile fun run that preceded the 5K was ending. The turnaround point for that run was only a few blocks from the trash can containing the bombs.
The FBI declined to comment Monday on why two of the three pipe bombs inside the garbage can did not explode.
The race, in its third year, attracted more than 1,600 runners. Spectators added to the crowd. While canceled Saturday, the race will go on next year, organizers said. As for this year, they just consider themselves fortunate.
"Thank God that nobody was hurt," Costello said. "That was just luck."
