Aflac, one of the largest insurance companies in the United States, says hackers stole an unknown quantity of its customers’ personal information from its network during a cyberattack earlier this month.

Insurance company Aflac disclosed this week that cybercriminals breached its U.S. network and may have accessed customers’ personal information, the latest in a string of cyberattacks on insurance companies announced this month.

Aflac recently revealed that hackers stole its customers' data in a cyberattack. Details remain scarce, but the company says it "was caused by a sophisticated cybercrime group" that's targeting the insurance industry.