The exchange has placed restrictions on the accounts to comply with AML laws as suspected funds linked to EU crypto theft passed through it's accounts. No customer funds were affected and they're working with regulators on possible recovery.
This incident did not originate on the Kraken platform, and we’re actively investigating reports that some of the assets were subsequently moved through accounts on our platform,” Kraken told Cointelegraph. “We’ve restricted the accounts in question and are working with law enforcement to support recovery efforts.”
Kraken said its security systems had not been compromised and no customer accounts had been taken over. The statement gave no account count or value of restricted assets, leaving the amount available for recovery unclear.
ZachXBT puts the incident at more than $133 million.
https://thedefiant.io/news/hacks/kraken-restricts-accounts-amid-suspected-133-million-plus-eu-theft