As said by CCN:
“Intrigue abounds around the allegedly Singapore-based WEX exchange, whose ownership and activities have both been called into question in recent months.”
One key thing to look at was the exchange listing a much higher market price for Bitcoin and strangely overcharging for USDT. Prior to this, an interesting report on the exchange written by Conor Maloney which partly explained:
“WEX is a rebranded version of the BTC-e exchange which was shut down in connection to a multi-billion dollar money laundering operation with a Russian national named Alexander Vinnik reportedly charged in connection with the criminal operation.