Even as federal authorities issued an alert warning U.S. law enforcement officers that terrorists are continuing to conceal explosive devices in thick soled shoes, a regional law enforcement agency followed up Thursday with a warning that one manufacturer's beach sandal can hold liquid explosives and a sharp implement in its heel, ABCNews.com has learned exclusively.

According to a bulletin issued originally last spring and reissued yesterday the "Dram Sandal" by Reef, is capable of holding approximately 2-3 ounces of liquid in a hidden compartment, located in the heel of each sandal. The Dram Sandal became available March 1, 2007, and can be purchased online and at most shoe stores, the bulletin stated.

Photos: Explosive Footwear

"The Reef Company, which is a designer and distributor of casual apparel and footwear, has developed several sandals with bottle openers concealed in the heel of the sandal" the bulletin reads. "The most recent line of Reef Sandals is the Dram Sandal. The Dram Sandal contains a flask embedded into the sole of the sandal and is marketed as a 'Polyurethane encapsulated canteen in heel with screw cap.' In addition to the hidden plastic canteen, the sandal comes complete with a mini funnel, church key/bottle opener and a visual gauge embedded in the sole to show how much liquid is remaining in the hidden compartment. The hidden compartment in the Dram Sandal, which was primarily made for storing beverages, could intentionally or unwittingly be used to store and transport liquid explosives."

The bulletin was reissued in the northeast United States and circulated throughout the law enforcement community just one day after an October 24 bulletin by the Department of Homeland Security and the FBI. That bulletin noted that European authorities in September 2007 discovered a pair of shoes that were used to smuggle electric blasting caps across international borders for use in a terrorist attack.

"A recent terrorist incident involving the international smuggling of electric blasting caps highlights the continuing use of modified footwear as a concealment method for explosive devices," stated the DHS - FBI Bulletin "Terrorist Use of Modified Footwear to Conceal Explosive Devices."
In 2001 convicted "shoe bomber" Richard Reid devised a shoe improvised explosive device (IED), which consisted of 10 ounces of homemade high explosive concealed in his high topped shoes. He successfully passed through airport security and attempted to blow up an American Airlines plane flying from Paris, France, to Miami, Florida. He was subdued by passengers.

This attempt led to the Transportation Security Administration (TSA) policy of X Raying the shoes of all passengers boarding US flights.

The Dram Sandal holds about 2 ounces less than what Reid's shoe IED contained. The amount the sandals could contain is nonetheless sufficient to cause considerable damage. 

In a 2006 extremist plot thwarted by United Kingdom officials, terror suspects allegedly intended to use liquid explosives to simultaneously attack multiple aircraft while in flight from London's Heathrow airport to the US.

The regional bulletin noted that neither local law enforcement nor the FBI possessed any information "to indicate the Dram Sandal will be exploited by extremists." However, it said, "all sectors are reminded of the potential threat that exists from this sandal and advised to be vigilant of its contents if encountered.

"It would only require small quantities of various liquid explosives or fuels to generate the force necessary to produce an explosion, capable of causing a hole in an aircraft or seriously disabling it. With the continued focus on air transportation by al Qaeda and other likeminded groups, TSA officials should be aware and become familiar with this specific sandal."

A similar advisory to be alert was included in the DHS-FBI bulletin based on the shoes seized in Europe.

"The shoes were modified in a manner that would make it difficult for security personnel to distinguish them from normal shoes visually." They were not worn, the bulletin said, but transported by bus concealed in luggage.

"The shoes—made of leather with thick rubber soles—were modified so that the insole of each shoe could be removed for access to the  hollow interior of the rubber sole," according to the bulletin.

"Electric blasting caps were placed inside the hollow rubber sole, and the insole was glued to the rubber sole to appear as if  the shoe was never modified," it continued. "The blasting caps—each measuring about two inches in length—were individually wrapped in paper, possibly to protect them from the glue used when the shoes were reassembled."

The FBI told the Blotter on ABCNews.com that the bulletin was sent out as part of the routine information sharing between various members of the law enforcement and intelligence communities.
"The FBI and DHS routinely send out these bulletins to our law enforcement and intelligence community partners to share information," said Senior Special Agent Richard J. Kolko, Chief of the National Press Office. "It is not related to a threat, but is provided in order to allow officers on the streets to be alert to items that appear routine but may not be, as they go about their daily duties."

The bulletin itself noted there was no "specific, credible" current threat information indicating "that terrorists plan to use this concealment method in the homeland.' But also noted that the incident "highlights the continuing use of modified footwear as a concealment method for explosive devices."

As such, the attempt to smuggle blasting caps is but the latest in a series of attempts by terrorists, whether autonomous or Al Qaeda, to either smuggle explosive components in shoes, socks, gel bras and other items of clothing, or conceal complete improvised explosive devices in their clothing.

The most infamous in recent years occurred on December 22, 2001. On that day Richard Reid boarded a Paris to Miami flight wearing a pair of dark colored, high topped shoes. Into the waffle-style soles he had woven a high explosive and a length of detonator cord. He  linked his device to a paper wrapped homemade high explosive  initiator . Alert passengers and crew members spotted him bending over in an attempt to ignite  a fuse and subdued him. On December 4th 2003 Reid was convicted in Boston federal court of attempting to use a weapon of mass destruction against US citizens, and other charges.

Reid, a 29-year-old British citizen, was sentenced in January 2003 to life in prison on three counts: one of attempted use of a weapon of mass destruction against U.S. nationals outside the United States and two of interference with flight crew and attendants using a dangerous weapon. He was also ordered to pay a $2 million fine and sentenced to consecutive 20 year terms on four other counts and a 30 year term on an eighth count.

Since Reid's attempt airports in the United States have implemented a 100 percent X-ray inspection policy for footwear. The bulletin noted that some foreign airports do not, however, check all passengers' shoes. In addition, terrorists have continued to refine their attempts to use footwear.

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But by the close of 2003, US authorities issued another alert, one that was broadcast by ABC TV and radio and published on ABCNews.com. That alert warned of terrorists using socks soaked in explosives and hung from a cord around a terrorist's neck as a way to avoid bomb sniffing dogs, and conceal the explosive from airport authorities. The bulletin featured a pair of blue socks it said were found by British anti-terror police  in November.  They were discovered during  a series of raids.  Forensic tests on the socks allegedly found they had been laced with several explosives, including TNT, PETN (similar to Semtex) and RDX. 

While it is not clear exactly in what capacity the individual may have been using the socks, it is possible the suspect may have been suspending the socks from around his/her neck or under outer garments in an effort to conceal explosives carried in them," said the bulletin. "It also cannot be discounted that these tethered socks were components of an improvised explosive device in the making. "

At the same time the alert on the explosive soaked socks was issued, the FBI weekly circular to law enforcement warned that recent intelligence "indicates that terrorists continue to develop plans to hijack aircraft and use them as weapons" despite improved security and vigilance since the Sept. 11, 2001, attacks.

In August 2006, a cell of al Qaeda inspired and linked alleged British terrorists were stopped in the final stages of a plot to board a series of US airliners bound from Heathrow to the US and ignite their bombs in flight. Elements of the devices they planned to use were concealed in the bottoms of sports drink containers they intended to smuggle aboard.

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