No details were ever confirmed, no one was named, just that 'people familiar with the matter' said that 'Chinas regulators are studying measures to limit transactions that use bitcoin'.
One rumor and people panic and start selling coins and the price drops several percent.
I guess Bitcoin is not as solid as I thought and the price is still heavily based on speculation.
The correction was expected after the price had risen nearly a hundred dollars over the last few weeks. That's why even an unconfirmed rumor may cause a drop like what we've witnessed. The price would still correct sooner or later, just like it happens with any other asset however solid that asset might look, even with gold. There's no rose without a thorn.