Napolitano: U.S. Screening Cargo, Passengers Coming From Japan

Department of Homeland Security Secretary Janet Napolitano says the U.S. is conducting radiation checks on passengers and cargo coming from Japan in the wake of the disaster that has left nuclear facilities damaged.

"There is screening going on and it occurs at a variety of different ways. It depends on whether you're talking about passengers or cargo, where it's departing from," Napolitano said. "We have seen no radiation, by the way, even on coming cargo or passengers that comes close to reaching a harmful level."

Napolitano says despite the fact no contamination has been found in the U.S., the screenings will continue.

"We think working with the Department of Health and Human Services, working with the Food and Drug Administration, working with the Environmental Protection Agency there will continue to be this kind of monitoring," she said.

The secretary called the screenings an "exercise of caution."

FOX News producer Mike Levine contributed to this report.