After 39 years, the Harvey's Casino Bomb remains "one of the most unique improvised explosives devices the FBI has ever come across"

The FBI's website's "History" section has the incredible story of the "Harvey's Casino Bomb," worthy of a 1980s crime thriller. The massive bomb was built by a 59-year-old gambler named John Birges, Sr. who lost a lot of money at Harvey's Casino in Lake Tahoe. The bomb contained "nearly 1,000 pounds of dynamite and eight triggering mechanisms, which made it virtually undefeatable," says the article.

On the morning of August 26, 1980, Birges and his two sons dressed in white jumpsuits, and rolled the bomb, disguised as a copy machine, into the casino.

A note left with the bomb—titled STERN WARNING TO THE MANAGEMENT AND BOMB SQUAD—began ominously: "Do not move or tilt this bomb, because the mechanism controlling the detonators in it will set it off at a movement of less than .01 of the open end Ricter [sic] scale."

"Do not try to take it apart," the note went on. "The flathead screws are also attached to triggers and as much as ¼ to ¾ of a turn will cause an explosion….This bomb is so sensitive that the slightest movement either inside or outside will cause it to explode. This bomb can never be dismantled or disarmed without causing an explosion. Not even by the creator."

Birges wanted $3 million in "return for supplying directions to disconnect two of the bomb's three automatic timers so it could be moved to a remote area before exploding safely." But instead of paying the ransom, the FBI tried using explosives to disarm the bomb. "The plan was the best one available at the time, but it didn't work. The bomb exploded, creating a five-story crater in the hotel." No one was killed.

Birges was caught and died in prison in 1996.