AS 40,000 RUNNERS barreled down Broad Street, four law-enforcement officials were in a race of their own. The prize was more than a medal and bragging rights - it was a man's life.

FBI Special Agents Erik Negron, Tom Powell and Brian Hoffman, as well as Philadelphia Police Officer Matthew Fleming, took action Sunday morning during the Broad Street Run, working together to revive a 35-year-old man, one of two runners who had gone into cardiac arrest, authorities said last night.

It happened in a split-second, according to Special Agent J.J. Klaver, an FBI spokesman. A little after 9:30 a.m., as the runner reached Lehigh Avenue - about 2 miles into the course - he dropped to the pavement.

A cop standing nearby sent a frantic bulletin over police radio, requesting a medic.

But the three special agents and Fleming - an interagency team working security for the event - were closer, Klaver said. And they sprung into action.

Hoffman and Fleming, both trained EMTs, began administering CPR to the runner, who had no pulse.

Luckily, part of the group's on-hand equipment was an emergency defibrillator, which Fleming used to kick-start the man's heart, Klaver said.

Medics arrived soon after and helped stabilize the runner, who was recovering last night.

"When you have that kind of training - and it sounds strange - you think, 'I want to be there when someone needs it,' " said Klaver, a former EMT himself.

Klaver said the men were grateful that they were able to get to the runner in time.

"Any time we can help someone positively like this," he said, "it beats the other stuff we encounter on the job."

Philadelphia Police Chief Inspector Joe Sullivan, who, as head of the Homeland Security Unit, oversaw the department's presence at the race, said rescues like Sunday's demonstrate why he stresses cooperation among agencies.

"We were all really fortunate," he said. "We had all the assets in the right place at the right time, and everything went really well."

In fact, Sullivan himself had a similar scare later that morning, about 8 miles down the road: A 27-year-old man, after taking his final steps across the finish line, collapsed in front of him.

"It was a surreal moment," Sullivan said. "He went down hard; we didn't have time to even catch him."

Like the 35-year-old in North Philly, the runner had gone into cardiac arrest.

And, as in the earlier incident, the injured runner had help nearby, this time in the form of a team of medics waiting at the finish line.

The 27-year-old was treated at the scene and later was taken to Temple University Hospital, Sullivan said. He, too, was recovering last night.

Medical-privacy laws have prevented Fleming, Hoffman and the other agents from contacting the man whose life they saved, Sullivan said, adding that all four men were "beyond relieved" that they were able to help.

"It's a pretty great feeling to say you helped bring him back, considering that, at one point, this guy had no heartbeat," Sullivan said.

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