Highly unstable, peroxide-based explosives such as TATP and its sibling hexamethylene triperoxide diamine or HMTD, have been used in terrorist bombs for decades. TATP first gained notoriety after the Sept. 11, 2001, attacks when Richard Reid, known as the shoe bomber, unsuccessfully tried to detonate a TATP-triggered explosive during a Paris to Miami flight in December 2001. TATP was also used in the 2005 London bombings that killed 56 as well as in the November 2015 attacks in Paris.

TATP’s ingredients, such as concentrated hydrogen peroxide and acetone, are extremely easy to procure and cook into an explosive. But the powdery substance is highly volatile and potent, earning it the nickname “The Mother of Satan.” A few grams of TATP can easily blow off fingers, while concentrated pounds of it are devastating.

According to an Army Explosive Ordnance Disposal Technician, who requested his name be withheld because of his current employment, TATP-based explosive devices are rarely seen in war zones such as Iraq and Afghanistan because of how temperamental the material is and stable, military-grade explosives are readily available. TATP, he said, has become a staple in Europe because of its accessible ingredients and how they raise little suspicion when purchased individually.