It seems to be some GIANT investors manipulating the bitcoin market.
Any ideas??

It's not just today, but the whole last weeks that the price started to bounce up and down due to the hard fork speculations. If you look closely at how the price behaved, then you'll notice that each time the price went under $1000, it found its way back up to the $1000 level. Current drop to under $1000 isn't anything special. It will bounce back up to over $1000 in the coming days, no worries. Instead, you could even look to buy back some coins in case you cashed out profits around the $1200 level.