Explosives found on planes bound for US

Security officials on both sides of the Atlantic are now investigating whether the packages found on international cargo flights were part of a "dry run" for a wider global mail bomb plot.

The packages at the centre of yesterday's security alert originated in Yemen, considered by security sources as a major centre of al-Qaeda activity. The packages were destined for two synagogues in Chicago.

Last night US President Barack Obama confirmed that both packages "contained explosive materials", adding the terror plot posed a "credible" threat.

Mr Obama said he would be seeking greater "co-operation" with the Yemeni authorities in order to tackle the activities of an al-Qaeda offshoot, and urged the public to be "vigilant".

"We will continue to pursue additional protective measures for as long as it takes to ensure the safety and security of our citizens," he added.

"I have also directed that we spare no effort in investigating the origins of these suspicious packages and their connection to any terrorist plotting. Although we are still pursuing all the facts, we do know that the packages originated in Yemen.

"We also know that 'al-Qaeda in the Arabian Peninsula', a terrorist group based in Yemen, continues to plan attacks against our homeland, our citizens and our friends and allies."

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But later the Yemeni government expressed astonishment at reports linking it to the two explosive packages found on cargo planes bound for the US.

In a statement the government said there were no UPS cargo planes that had taken off from Yemen, or any indirect or direct flights to British or American airports, however the government added that it is co-operating with the US, British and Emirates parties.

US fighter jets last night escorted an Emirates flight 201 into JFK Airport, New York, because cargo originating from Yemen was on board.

Meanwhile, in the UK, the government's Cobra crisis committee, which gathers together officials from various departments, met last night to discuss its response to the security incident.

The alert was first raised when suspicious packages were found by UK intelligence and law enforcement officials at East Midlands Airport, south west of Nottingham, and by United Arab Emirates officials in Dubai in the early hours of yesterday morning.

The discoveries prompted US national security officials to alert Mr Obama to a "potential terrorist threat". The two packages were addressed to synagogues in the Chicago area.

The package in Britain contained a toner cartridge with attached wires and powder, confirmed as containing explosives. The device was found during routine screening of cargo, prompting authorities to scour three planes and a truck in the US.

Police in the UK evacuated a freight distribution building at East Midlands Airport after the suspicious package was reported at 3:30am.

A first search by police and military bomb experts failed to find anything suspicious, but a decision to declare the all-clear was reversed and a further check is understood to have revealed that a Hewlett Packard printer in the box contained a hidden suspicious device that gave cause for greater concern.

It is understood the device was "cleverly disguised" and appeared to have been linked to a mobile phone. The device was then split in two and sent for detailed investigation by the authorities. It is understood that the East Midland's device was similar to the one found in Dubai. However, officials are as yet unclear as to how the devices would be detonated.

The cordon that had been placed around East Midlands Airport during the day was finally lifted at 5:35pm, an airport spokesman said.

Presidential adviser John Brennan said that the explosives "were in a form that was designed to carry out some type of attack".

Sarah Furbank, a passenger who was about to board a plane out of East Midlands Airport, said that she had noticed an increased security presence.

There were "quite a few police cars round the edge" of the airport, Ms Furbank said. "Apparently, there was an incident earlier according to staff but they didn't go into detail"

As a result of the discovery, direct flights from Yemen to the UK were suspended by Home Secretary Theresa May.

Responding to the incidents, the White House said in a statement: "The president directed US intelligence and law enforcement agencies, and the Department of Homeland Security, to take steps to ensure the safety and security of the American people, and to determine whether these threats are a part of any additional terrorist plotting."

An official later said the potential plot had been uncovered as a result of intelligence from an "ally abroad", now confirmed as Saudi Arabia and that intelligence personnel had been monitoring a suspected plot for days.

Aviation terrorism expert Chris Yates said that the alert highlighted weaknesses in airport security which terrorists could be trying to exploit.

He added: "Cargo security has always been the Achilles' heel of the aviation industry, in so much as it's very difficult to examine with, say, an X-ray device, certain types of containers that are used on cargo jets. There are a bunch of issues there, how do you examine in-depth everything that might be contained in these containers, because it might be multiple objects from various different sources.

"There's a process that we employ worldwide, which requires that the supply chain does that security check before containers are delivered to the airport. But can you be absolutely sure that the supply chain is secure?"

Yemeni officials said they launched a terrorism investigation and Scotland Yard said its investigators were testing a number of items seized from the plane at East Midlands Airport. In the US, searches were conducted in Philadelphia, Newark, in New Jersey, San Francisco, Portland in Maine and New York City. The packages, though not the planes, originated in Yemen and were being sent via shipping companies United Parcel Service Inc and FedEx.

Transportation security administration spokeswoman Kristin Lee said the planes in Philadelphia and Newark were moved away from terminal buildings, while law enforcement officials swept for any potential devices. Two Philadelphia jets belonging to UPS were searched but nothing suspicious was found.

New York Police Commissioner Ray Kelly said that the NYPD removed a package from a UPS truck in Brooklyn, tested it for possible explosives and found it not to be dangerous. The package was an envelope that came from Yemen, appeared to contain bank receipts, and was addressed to the JP Morgan Chase bank in Brooklyn, Mr Kelly said. The package arrived on a plane that landed at JFK Airport, he said.

Mike Mangeot, a spokesman for Atlanta-based UPS, said two planes in Philadelphia that had come from Cologne, Germany, and Paris were being investigated. "Out of an abundance of caution, those aircraft have been isolated, and they are looking into the shipments in question there," he said.

A third plane had arrived in Newark, New Jersey, from East Midlands Airport. That plane was cleared and flew to UPS' main hub in Louisville, Kentucky, on its usual route, Mr Mangeot said.

The Jewish Federation of Metropolitan Chicago said it was aware that it had been targeted: "We were notified this morning that synagogues should be on alert and we are taking appropriate precautions and are advising local synagogues to do likewise."