I think there is a misundertanding here. Do they ban it totally or just for illegal purpose?
It is just speculations that has been used today to manipulate the market and I'm sad that they succeeded to do that. Their main objective was to cause retail traders to do panic selling. I hope you didn't!
That is right the panic on the market started, people rushed selling their Bitcoins, the demand for this cryptocurrency decreased. As the result BTC and all altcoins together with it lost a lot. Rumors, especially negative information can always cause dips.