A cyberattack on Arizona’s court system compromised personal information belonging to more than 1 million people, with officials believing the breach began after a court employee clicked on a malicious link in an email.

The Arizona Supreme Court said data belonging to 1.3 million people with unpaid court fees, fines and restitution payments related to traffic and criminal violations were copied in the attack. The records date back as far as 30 years.

The attackers also accessed records involving nearly 30,000 active and inactive orders of protection and 150,000 reports dating back to 2010 from a foster care board that makes recommendations in cases involving allegations that parents are unfit or unable to care for their children.

Court technology staff detected the attack on 24 September and shut down the affected backup server about two hours later. The court has since notified people whose information was compromised.

“We don’t have any evidence it has been used or shared” since the attack, state Supreme Court spokesperson Alberto Rodriguez said on Tuesday.

The incident remains under investigation and has not affected or delayed any court proceedings, Rodriguez said.

No records were altered or deleted, and the attackers did not obtain information involving jurors, witnesses or court employees.