Mysterious Flash Crash on CoinDesk, within the value of Bitcoin

CoinDesk shows a mysterious Flash Crash that it is not known where it came from and how it was generated, because in the indexes on which CoinDesk is based, they have not suffered movements of this type.
CNBC has reported a mysterious event, specifically a flash crash in the price of Bitcoin. This happened, according to this medium, at 9 in the morning in the United Kingdom. According to the CoinDesk index, Bitcoin went from $ 4.867 for each Bitcoin unit and went for a few seconds to be worth $ 4.200. It represents a loss of value of $ 600 (12% of the total value), but in a very short time, just a few seconds later, it returned to $ 4.780. This event lasted only ten minutes and apparently has no effect on the value of this coin.
It should be noted that CoinDesk obtains the values for its value graph from exchanges such as BitStamp, Coinbase, itBit and OKCoin. The funny thing is that none of the indexes show the same incident and this problem is not seen in CryptoComparte.com, which does the monitoring functions of the industry. It is quite rare that none of the exchange houses show data on this incident. From CNBC, an attempt has been made to contact CoinDesk to find out the reasons for this event, but no official data has been given.
It reminds us a lot of what happened in Ethereum last June, where a similar event also occurred. It is clear that these events are not normal and are often investigated. It could be some kind of CoinDesk glitch, but beyond that we can't say much more. The peculiar thing is that none of the exchange houses on which this index is based have the same or similar graph, therefore the situation becomes even more strange. We'll see if the reason is discovered.
