There had been conflicting reports about whether either of the two intercepted packages tested positive for explosives. British and US officials initially reported that tests for explosives were negative, but other American law enforcement officials said at least one, possibly both, contained explosives. In a statement late Friday, British officials said only the "suspect package" was "currently being examined."
British Home Secretary Theresa May said that "a suspect package was discovered during a search of a cargo flight at East Midlands airport." May said the package originated in Yemen and was addressed to a destination in the US.
A FedEx official confirmed that a suspicious package shipped from Yemen had been "confiscated" at the FedEx facility in Dubai. Local authorities confiscated the package in cooperation with the FBI.
In a statement, the Department of Homeland Security said it was taking steps to enhance air security. "Some of these security measures will be visible while others will not," said the statement.
"The public may recognize specific enhancements including heightened cargo screening and additional security at airports. Passengers should continue to expect an unpredictable mix of security layers that include explosives trace detection, advanced imaging technology, canine teams and pat downs, among others. As always, we remind the public to remain vigilant and report suspicious activity to local law enforcement."
A spokeswoman for the Jewish Federation of Chicago told ABC News the federation was alerted this morning and passed on the alert, advising local synagogues to take security precautions. She also said the group was not one of the targets.
The FBI's Chicago office said that the packages "in question" had been addressed to two Chicago locations, but would not provide further details. The FBI "notified the targeted institutions" by phone this morning, according to a spokesman. The White House said that the synagogue across the street from the president's home in Chicago was not one of the synagogues targeted.
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The Anti-Defamation League released a statement that said it had learned from "law enforcement sources" of a reported threat to Jewish institutions in packages shipped from the U.K., Yemen and Saudi Arabia, and that it had sent notice to Jewish organizations across the U.S.