According to EA the games being purchased most are Fifa 15, FarCry 4, Assassin’s Creed Unity, Assassin’s Creed Black Flag, Watch Dogs, and Fifa points. EA is looking into all reports and have said that there has not been a breach of security.
EA believes the best course of action right now is to change your ID and password as a precaution until everything is figured out and to report any activity you feel is unauthorized to an EA Game Advisor. If you haven’t already it may be a good time to turn on login verification.
If your account has been hacked you can create a new account to contact EA as well.