DES MOINES, Iowa (AP) — Pension payments stolen from the accounts of more than 100 Iowa public employee retirees have been returned to them, state officials said Thursday.

The Iowa Public Employees' Retirement System said 103 accounts were compromised in mid-October. The system serves workers for state and local governments and school districts. It sends payments totaling about $1.8 billion a year to 115,000 retirees.

Hackers obtained stolen Social Security numbers and birthdates, used the information to register for online account access and diverted the payments to different financial institutions, retirement system spokeswoman Judy Akre said. The system learned of the crime Tuesday, she said.

She would not give a specific amount for how much was stolen from the accounts. She said it was "several hundred thousand dollars."

Only accounts that had not previously established a username and password for their online access were affected, Akre said. Officials have not determined where the hackers obtained the stolen information, but do not think it was taken directly from the retirement system.

No arrests had been reported as of Thursday afternoon.

The crime was reported to the FBI and the Iowa Division of Criminal Investigation.

"We're meeting with people from both agencies right now," Akre said Thursday morning.

The system has reissued the payments to the correct financial institutions so the retirees will not lose money, she said. The retirees are being asked to check with their financial institutions to ensure the October payments were properly credited.

"That process takes a few days, so those members will have their funds either on or before Nov. 7," Akre said.

A message left Thursday for the Iowa Division of Criminal Investigation in Des Moines was not immediately returned.

A spokesman for the FBI in Omaha, which covers Iowa as well as Nebraska, said the agency is aware of the pension payment thefts and is working with Iowa law enforcement authorities. He declined to comment further.