Rumors that the Chinese government is considering banning cryptocurrency exchanges in China has made Bitcoin prices drop in minutes.
SOURCES:
Coindesk - https://www.coindesk.com/report-casts-doubt-future-chinas-bitcoin-exchanges/
Coin Telegraph - https://cointelegraph.com/news/breaking-bitcoin-altcoin-prices-tumble-up-to-25-on-china-exchange-ban-rumors
Tech Crunch - https://techcrunch.com/2017/09/08/bitcoin-price-drops-following-report-that-china-is-going-to-shut-down-local-exchanges/