A member of the NYPD counter terrorism division, stands as...

A member of the NYPD counter terrorism division, stands as part of a gauntlet on the Macombs Dam Bridge not far from Yankee Stadium as part of a "dirty bomb" drill last week. Credit: Craig Ruttle

It was only a drill but last week's "dirty bomb" exercise succeeded in intercepting all potential radiological devices before they entered New York City, officials said Monday.

The five-day Securing the City drill also captured nine "terrorists" who were trying to smuggle the radioactive materials into the five boroughs from Suffolk, Nassau and other surrounding counties, the NYPD said.

While federal Department of Homeland Security officials will give a final assessment, NYPD spokesman Paul Browne said things seemed to have gone smoothly.

"Initially it appears to have gone very well, with good communication among participants and a [high] success rate," he said.

NYPD officers, along with counterparts from Long Island, Westchester County, New Jersey and Connecticut, spent five days with radiation detectors searching for Cesium carried by other officers posing as terrorists. Some 153 radiation sources that were part of the exercise were detected, while cops also got readings on 35 real-world sources, mostly people who had undergone radiation treatments. The small amounts of Cesium carried by the fake terrorists posed no health hazard.

Another group of NYPD counterterrorism officers participated in an unrelated "Red Cell" operation in which they uncovered 16 radioactive sources carried in backpacks in the city subway system, said police.

"At no point during exercise play were the 'terrorists' successful in bringing a radiological device into New York City from the surrounding region," an NYPD statement said. "Moreover, all 'terrorists' were apprehended by the conclusion of the fourth day of the exercise."Dirty bombs, which are nonnuclear, but which can spew contaminating radiation into an urban area, are viewed as a potential terrorism threat.

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