We got confirmation from MONA developers regarding the attack on blockchain. Fraud coins (nonexistent) has been deposited to Exchanges. So, we have to close deposit/withdrawal for indefinite duration. Further actions depends solely on the response from developers.
Isn't increasing deposit confirmations an option, even something super high like 12-24 hours (not sure how many blocks that would be, but it would be a long time to sustain a block withholding attack and therefore prohibitively expensive)
Also, has anyone heard if/when the bittrex wallet will re-open?