Discovery of suspicious cargo prompts Philadelphia search

President Obama said Friday that two suspicious packages sent from Yemen and bound for the United States contained hidden explosives, discoveries that touched off a wide-scale terrorism alert including the search of two cargo planes at Philadelphia International Airport.

Obama said the packages, which were intercepted in the United Arab Emirates and England, had been addressed to "two places of Jewish worship in Chicago."

"The detail was specific and credible," said U.S. Rep. Charles Dent (R., Pa.), ranking member of the Homeland Security Committee's subcommittee on transportation security and infrastructure protection. "These were real threats."

In addition to the two planes in Philadelphia, authorities searched a cargo plane at Newark Liberty International Airport and an Emirates commercial flight that two Air Force F-15 jets escorted to John F. Kennedy International Airport in New York City. All four planes had cargo originating from Yemen, authorities said, but nothing of concern was reported found.

Police also stopped and searched a UPS truck in Brooklyn, N.Y., but found nothing dangerous.

In Philadelphia, no inbound or outbound passenger flights were affected by the searches, airport spokeswoman Victoria Lupica said.

The UPS planes were taxied to a remote area of the airport to be inspected. Police in Newark and Philadelphia also evacuated the cargo terminals at both airports "out of an abundance of caution," according to the Transportation Security Administration.

The investigation was triggered by the discovery of a suspicious powder in a toner cartridge shipped from Yemen via UPS, a federal law enforcement source told The Inquirer. The cartridge, which had wires attached, was detected during an early-morning screening at East Midlands Airport north of London. The U.A.E. package reportedly was found at a FedEx facility in Dubai.

The device discovered in England "may be some sort of" improvised explosive device, a source told The Inquirer. U.S. officials told the Associated Press late Friday that the device may have contained PETN, the explosive used in an attempted attack on a commercial airliner on Christmas.

Intelligence personnel had been monitoring a suspected plot for days, officials said. The packages in England and Dubai were discovered after a Saudi Arabian intelligence operative picked up information related to Yemen and passed it on to the United States, one official told the Associated Press.

The packages intercepted in England and Dubai would have arrived in the United States about 4 or 5 a.m. Friday. Concerned officials decided to search certain flights for similar devices.

"The decision was not based on specific information," an official told The Inquirer, "but out of concern about potential vulnerabilities."

Federal agents still are trying to track down similar packages, but reports of as many as 20 devices coming from Yemen are misleading, a federal official briefed on the case said.

"We're looking for packages, but it's hard to put a number on it," the official said. "It depends on how far back you go in terms of looking for packages sent from Yemen to the U.S."

Dent said he thought it was significant that the packages were sent on cargo, rather than passenger, planes. "It's probably safe to say there's been less security attention paid to cargo aircraft," he said. "It's quite clear that our enemies are probing our defenses."

Since the Sept. 11, 2001, terrorist attacks, federal officials have grappled with how to inspect air cargo without bankrupting its carriers or clogging a vital route of global trade. A 2007 Congressional Research Service report found that slightly more than a quarter of the value of goods shipped to the United States arrived by air.

"It has been generally argued that full electronic screening of all air cargo . . . is likely to present significant logisticcq and operational challenges," the report said.

At the time, all passenger baggage was required to be screened, the report said, but the TSA was reluctant to say how much air cargo was inspected in a given year.

"I don't know if they're able to screen 100 percent," said Wojtek Wolfe, a national security expert and professor at Rutgers University-Camden. "It's always a balance between security and economy."

Wolfe echoed the Congressional Research report when he noted that terrorists likely would not find much value in bombing air cargo carriers such as UPS. Rather, he said, he suspected the explosives might have been meant to be assembled by someone in the United States into a larger device.

The devices also could have been sent as a test run of the air cargo system's detection capabilities. "Terrorist organizations are continually doing penetration testing," he said.

After the discovery of the packages, the government of Yemen "launched a full-scale investigation," said Mohammed Albasha, a spokesman for the Yemeni Embassy in Washington. He noted that no UPS cargo planes land or take off in Yemen, but sources said UPS uses subcontractors there.

UPS, which operates in 200 countries and describes itself the world's largest package-delivery company, said Friday it would stop accepting packages from Yemen. The company's main hub is in Louisville, Ky., and Philadelphia is one of four U.S. regional hubs.

Yemen, the ancestral home of Osama bin Laden's father, is the base of operations for al-Qaeda on the Arabian Peninsula, a branch known for targeting Western interests in Yemen and Saudi Arabia. U.S. officials credited Saudi authorities Friday with helping them realize the "imminence of the threat emanating from Yemen."

One of the group's key figures is Anwar al-Awlaki, a radical Yemeni American cleric who has been linked to accused Fort Hood gunman Maj. Nidal Hasan, and the young Nigerian man who attempted on Christmas Day to down a Detroit-bound flight with explosives hidden in his underwear.

John Brennan, the president's counterterrorism adviser, was not prepared to lay blame for the devices Friday but signaled that the group was a strong suspect.

"Al-Qaeda in the Arabian Peninsula has been rather open in its venom towards the United States, toward Western interests," he said. "There are a number of individuals there that we're very concerned about, so we're looking at all possibilities."