Several factors played in this days price plummeting of the most popular cryptocurrency. Maybe because of those unpleasant news with respect to fears on regulatory crackdown; suspension of exchanges; banning from posting in facebook; issuance of waved of subpoenas and so forth. Also don't forget concerns about price manipulation of whales. But the most relevant factor i am seeing is that investors may just be ultimately loosing their trust that they can recover their capital that in turn a massive sell-off is the only notable thing to do.