The Department of Homeland Security on Wednesday warned airlines transporting passengers to the Sochi Winter Olympics to be on lookout for a new kind of threat: explosives contained in toothpaste tubes.

The warning, which contained no further information or specifics of a potential plot, is only the latest threat—real or perceived—targeting the games.

Chechen rebel leader Doku Umarov has called on terrorists to disrupt the Winter Olympics using “any methods,” and Russian security officials have been reportedly hunting “black widow” suspects who authorities fear want to carry out a suicide attack sometime during the next two weeks. Another group, Vilayat Dagestan, warned Russian president Vladimir Putin, “If you hold these Olympics, we will give you a present for the innocent Muslim blood being spilled all around the world: in Afghanistan, in Somalia, in Syria.”

While the spectre of a tube of toothpaste taking down an airliner may seem like only the latest half-brained attempt from terrorists hell-bent on sneaking bombs in the soles of their shoes or hidden in their underwear, history shows us why the authorities may be treating this one so seriously.

On Wednesday Oct. 6, 1976, anti-Castro Cuban terrorists took down Cubana de Aviación Flight 455 with a time bomb concealed in a tube of Colgate toothpaste. Seventy-six people died, many of them teenagers, as the plane fell into the sea just 11-minutes after takeoff on its way from Barbados to Jamaica. It wiped out the entirety of the 1975 national Cuban fencing team.

Thirteen years later, on Tuesday, April 18, 1989, Erin Bower, a five-year-old girl visiting a suburban Indianapolis-area Kmart, picked up a pump-style container of toothpaste while visiting the store with her family.

It exploded, and she let out an “amazingly blood curdling scream.”

The bomb tore off four of Bower’s fingers and a portion of her left hand, which was quickly packed in ice on its way to the hospital where doctors failed to reattach it. She lost sight in one of her eyes. But ultimately, she survived.

“It was a little more sophisticated than the average pipe bomb,” Charles A. Petersen of the Federal Bureau of Alcohol, Tobacco and Firearms said at the time. “It took some knowledge to construct it.” The alleged bomber, a local teenager named David Swinford, committed suicide two days after the blast. “I’m sure this boy had no idea what consequences were going to take place,” Erin’s mother said 20 years later.

In the years since, Americans have been frightened by plans that involved “a gel explosive in [a] toothpaste tube,” “a tube of toothpaste wrapped in duct tape” that led to an evacuation of JFK Airport, and a mysterious package from India containing four tubes, which appeared to be toothpaste before being loaded into a “bomb pod,” taken away, destroyed, and found to be…toothpaste.

As for the Sochi threat, the authorities aren’t saying much.

“It’s real. It’s real and we got very good information,” a source reportedly told CNN, adding, “It’s based on a credible source. We’re taking it seriously so are other countries taking it very seriously.”

Homeland Security released a statement that said the warning was issued “out of an abundance of caution.”

Americans who are already accustomed to removing their shoes, belts, and emptying their pockets before boarding a plane, took to Twitter to openly worry that toothpaste would be next to go at the TSA checkpoint.

On CNN, Mitt Romney, wondered why they hadn’t flagged it already.

Speaking to Wolf Blitzer, the former Presidential candidate and chairman of the Salt Lake City Winter Olympics, said, “You would wonder why they wouldn’t ban all tubes of toothpaste on flights going into the Sochi region.”