New York ? While some news organizations have tried to sneak material through airport screeners, ABC News thought bigger: the network smuggled depleted uranium into New York.

ABC conducted its operation to test how authorities are guarding against the possibility of a nuclear “dirty bomb” attack. Correspondent Brian Ross’ investigation will air as part of ABC’s Sept. 11 anniversary coverage next week.

Federal authorities are angry that they’ve had to spend time on ABC’s experiment.

“The U.S. Customs Service is engaged in a deadly serious business,” said its spokesman, Dean Boyd. “The American public wants us to focus on real threats, not fake ones.”

The story comes amidst controversy over stories in the New York Daily News and on CBS this week about how journalists tried to test airport security by trying to pass items that should have set off alarms.

ABC said it borrowed 15 pounds of depleted uranium from an environmental group, the Natural Resources Defense Council, to send on its journey. The network said it consulted with experts to make sure it was safe; the Customs Service said such material had less radiation than a typical chest X-ray.

Ross carried it by train from Austria to Istanbul, Turkey. The contents clearly marked, it was packed in a container with wooden horse carts and terra cotta vases and shipped overseas to New York. Through it all, the uranium went undetected.

“Seven countries, 25 days and 15 pounds of uranium,” Ross said, “and not a single question.”

The network was careful to obey all laws, federal and international, he said. The route and manner of transport followed a path outlined in court documents by an Osama bin Laden associate, who was investigated for his role in a plot to smuggle nuclear material, he said.

“One of our big concerns going into this was that we didn’t want to teach terrorists something they didn’t already know,” he said.

ABC sent the container from Istanbul, a known smuggler’s hotbed, to an address that had never received overseas shipping before because, in both cases, that should have made authorities suspicious, he said.

ABC and Customs differ on how authorities responded to a potential threat.

Of 1,139 containers on the vessel, the ABC package was one of fewer than a dozen identified for closer inspection before the ship even reached port, Boyd said. It was inspected by X-ray equipment and a separate device that tests for radiation and was found to pose no threat, he said.

Ross said, however, that the suitcase of depleted uranium would emit about the same radiation as live uranium would if it had been shielded in a lead-lined case. The container should have been opened and checked, he said.

“They missed it,” he said. “They could say that it was no danger, which is true because we made sure there was no danger. But I think that misses the point.”

Boyd insisted inspectors have ways to determine without opening the container whether the uranium was live.

“It was a fake threat that we were forced to divert resources and manpower to address,” he said.

Responded Paul Friedman, executive vice president of ABC News: “When did they divert any resources? They didn’t catch a thing.”

Friedman said the press played an important role in testing how well government is protecting its citizens.