Someone really wants to break the Tether - USD binding by panicking on the market.
No one really needs to break them, tether is not transparent in any way . They claim they hold dollars for the amount in circulation but I have not seen any audit documents from the team and last year they created a huge amount of coins in the market which coincided with the rise in bitcoin price to an all time high and still people trust the coin which is really weired as it can tumble anytime if the truth comes out .