CoinEx is based out of Hong Kong, and was recently forced to stop serving US customers as part of a settlement with the New York Attorney General which also required them to pay a $1.7 million fine.
CoinEx hacked for $70 million
Various blockchain watchers noticed suspicious transfers from a hot wallet known to belong to the CoinEx cryptocurrency exchange. CoinEx later confirmed a "security incident" involving "unauthorized transactions", and disclosed that around $70 million was stolen. Outside researchers have suggested that the thieves appear to be a part of the North Korean state-sponsored hacking group, Lazarus.