The FBI and the US Department of Homeland Security have issued a warning memo about terrorists implanting explosives in their body. Are there high-tech security checkpoints that can detect this new danger?

Security expert Glenn Schoen takes the threat of explosive implants seriously.

"It's not entirely new, but it's become hot news thanks to this summer's threat analysis and the latest information. So far, we've only seen external bombs worn close to the body, like the so-called underwear bomb. But it is a real concern that terrorists might be willing to sacrifice themselves by carrying a bomb inside their body."

Underwear
Two years ago, a young al-Qaeda sympathiser tried to blow up a plane with explosives concealed in his underwear. Dutchman Jasper Schuringa, a fellow traveller on that flight from Amsterdam to Detroit, overpowered the would-be bomber and became a hero.

International terrorists have now developed a bomb that can be implanted in the body. Aviation expert Benno Baksteen believes that America's warning of the ‘belly bomb' is unnecessary.

"I don't think it's a smart move. Of course it's reassuring that the Americans are following these developments closely. But it's enough for the general public to know that they need to remain alert. People will act accordingly, like the man who stopped the underwear bomber. Apart from that, you shouldn't publicise new threats too widely. As an ordinary citizen, they're not something you have control over."

The FBI memo includes all kinds of tips for recognising implanted explosives. Telltale signs include a swollen stomach, other unusual bulges and signs of pain during a body search.

Detonator
Schoen lists a number of ways in which a bomb can be attached or implanted. They include "things like a pacemaker, a colostomy bag, a tampon or a urine bag for patients who need such devices."

The security expert believes that surgically inserting the explosives is not the biggest obstacle, since terrorist organisations are known to have access to trained medical personnel. The challenge is that implanted explosives are difficult to detonate. Mr Schoen thinks no attacks involving explosive implants have occurred to date because terrorists have yet to come up with a suitable detonator.

Body scanning
At present, any terrorist with an explosive implant could hypothetically stroll through the body scanning equipment at international airports without hassle. Terrorists regularly determine their likelihood of getting caught by dispatching scouts carrying explosives or fake explosives who try to pass through scanners undetected.

Equipment at Amsterdam's Schiphol Airport only sees through clothing, not through skin, which means explosives inside the body would be invisible.

Mr Baksteen says airport security would need to resort to X-rays to see beneath the skin. That would be a costly venture. He wonders whether it's worth taking that extra step.
 
"You can never come up with a completely watertight system. Your best bet is to track down the people who are planning an attack as quickly as possible. That makes more sense than introducing exhaustive screening procedures for the world's two billion travellers."

Radio Netherlands World/   Klaas den Tek