More than 100 people who receive pensions from the Iowa Public Employees Retirement System or IPERS didn’t get their monthly payments on Tuesday.

It’s a case of identity theft and the FBI has been called in to investigate. According to KCCI, none of the 103 people affected had gone online to monitor their IPERS account and protect it with a password. Hackers then used Social Security numbers and other personal information to set up that online monitoring and redirect the pension checks for those 103 people.

IPERS regularly sends benefits to 115,000 retirees. Officials told The Des Moines Register monthly benefits had been reissued to the 103 people affected by the hack.