Coinbase Global said Thursday that it has refused to pay a $20 million ransom demand from cybercriminals who bribed the company’s overseas customer support agents to steal sensitive user data.The cryptocurrency exchange estimated that the incident could cost from $180 million to $400 million,

On Thursday, Coinbase confirmed that their systems were breached by unauthorized users and that internal company documents along with customers' personal data were accessed. The company was made aware of the breach via an email from the threat actor on May 11.

Coinbase, the largest cryptocurrency exchange based in the U.S., said Thursday that criminals had improperly obtained personal data on the exchange’s customers for use in crypto-stealing scams and were demanding a $20 million payment not to publicly release the info.