ST. PAUL, Minn. (AP) - Minnesota's health insurance exchange will repay about $500,000 in federal grant money after using it to prepare unused office space for its call center and other staff.

Reports say that state exchange chief Allison O'Toole wrote a letter this week to a legislative oversight committee saying office remodeling isn't an allowable use of the money.

The federal government has provided more than $5 billion to help states create health insurance exchanges. Minnesota has received $189 million in federal grants to establish its system.

According to earlier testimony from the acting administrator of the federal Centers for Medicare and Medicaid Services, Minnesota is one of at least four states to use federal grants for purposes that weren't allowed.