The unhinged conspiracy theory now known as "Pizzagate" has resulted in a man bringing an assault rifle to the DC bar named in the theory, according to local police.

"Pizzagate" claims that Democratic operatives placing orders at Comet Ping Pong were actually using code to talk about underage prostitutes.

This strange and convoluted conspiracy theory, which also involves allegations of occult rituals, has its origins in false accusations about the Clintons that began spreading in late October. The original theory claimed that the Clintons and other government figures were involved in a global human trafficking and pedophilia ring.

This one example shows how Trump supporters, members of 4chan and Reddit, and right-wing blogs in the US and in other countries combined to create and spread viral misinformation during the election season.

Here's what happened: