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The group , posing as Islamic radicals , stole data and released dozens of client log - in data , causing mayhem for the exchange , according to Bloomberg News .
 ( data breach: stole,  The group: attacker, data: compromised data) 
Locate the role in the text that participated in the event based on the event type and return it in the event list. 
 Option: Event type: phishing, data breach, ransom, discover vulnerability, patch vulnerability, Arguments type: vulnerable system, capabilities, vulnerability, number of victim, issues addressed, compromised data, damage amount, common vulnerabilities and exposures, victim, patch number, number of data, tool, discoverer, time, purpose, place, payment method, releaser, vulnerable system version, attacker, supported platform, patch, price, vulnerable system owner, trusted entity, attack pattern. 
Text: {0} 
Answer:
 ( data breach: stole,  The group: attacker, data: compromised data) 