661 BTC ($2.5 Million) Purchased in 1 Minute: Is This Unusual?

About 19 hours ago, it appears that 661 BTC ($2.5 million worth) was purchased in 1 minute on Bitfinex, according to this Reddit thread by u/coinsmash1. There's speculation that this might be related to The Dark Overlord hackers who are claiming they have 911 documents and are asking for payment. (See a post by @ura-soul about that here). Others think it's really not that abnormal, since it didn't change the BTC price by much.

My question: Do you see this as a big deal or is it really nothing major, but blown out of proportion? Curious to hear your thoughts on this.