PHOENIX -- A recent break-in at a storage unit could cause problems for thousands of people in Arizona.

Several hard drives containing information about clients of the Arizona Department of Economic Security were stolen in the October burglary.

The Department said it has no reason to believe that the intent of the burglary was to steal DES data or that anyone's personal information has been accessed by the thieves.

"While we do not believe that any of our families have had their information misused, out of an abundance of caution, we wanted to make them aware of the resources available to help them monitor their personal accounts and take steps to protect themselves if they feel their information has been misused," said DES spokeswoman Liz Barker Alvarez.

Several storage units, including the one leased by DES' Early Intervention Program, were broken in to and items ranging from furniture to electronics were stolen, Alvarez said.

"It really affected anyone who had applied, or been accepted, to the DES Early Intervention Program over the past several years," said Todd Davis, chief executive officer of Lifelock, a personal security firm headquartered in Tempe.

DES is sending letters to the families of up to 40,000 children whose information was stolen.

Anyone who gets a letter should place a fraud alert with the major credit reporting agencies, Davis said.

"What a fraud alert does is it tells anyone calling up your credit report that you have a concern that you are, or are going to be, a victory of identity theft," he said.

Things like full names and addresses may have been stolen from DES, Davis said.

"We call those the keys to the kingdom," he said. "Once they have that personal information on any individual, they are now susceptible to be victims of identity theft."

Besides watching their credit reports closely, Davis advised that people "go out at least once a year and request a work history with the Social Security Administration to make sure someone hasn't utilized (a) child's identity or your identity to go gain employment somewhere else."

If families have specific concerns, they can call the early intervention program at 602- 532-9960 or toll-free 888-439-5609 in areas outside Maricopa County.