The implants would not only escape detection, but according to security and medical experts, they could hide enough liquid explosives to bring down an airliner.
First it was the "shoe bomber," Richard Reid, who tried to detonate a bomb built into the bottom of his shoe.
Then in December, the so-called "Christmas bomber" allegedly tried to bring down a passenger jet with explosives that had been sewn into his underwear.
Now a new terror threat: surgically implanted explosives.
"It seems like these days, any of these things could really happen," said Beverly Hills plastic surgeon Dr. Stuart Linder. He specializes in body sculpting. He says the idea of silicone implants that could be injected with powerful liquid explosives is not only possible, but plausible.
"The consideration that a silicone-gel implant could be placed in a woman's body with an explosive internal device is something that is considerably possible," said Linder.
Tests on real plans have shown that even a small amount of explosive material could create small tears in fuselages. That could then lead to catastrophic failure. If an implant was loaded with explosives, it would be detonated with a hypodermic syringe to inject another chemical into the skin.
"With respect to a silicone implant, internally, some things such as PETN [pentaerythritol tetranitrate] could be placed in that, in something small -- it's only five ounces -- is plausible to be placed in a female's breast, and it could be ignited or activated and absolutely could cause a lethal explosion," said Linder.
Published reports say that British spies learned of the new threat when they detected increased chatter on Arabic Web sites.
Security experts say the surgically implanted explosives would go undetected by full-body scanners at airports.
According to Australian security experts, the best way to detect these new kinds of implanted explosives is with a very old-fashioned but highly effective detection method: the nose of a highly trained bomb-sniffing dog.