Fifth Third Bankcorp, the nation's 15th-largest bank, is selling its 11 Arizona branches to Milwaukee-based Marshall & Ilsley Corp., which also operates M & I Thunderbird Bank, Arizona's sixth largest bank. The sale price was not disclosed.

Fifth Third is leaving Arizona to focus on its core, which is the Midwest, say bank officials.

M & I Thunderbird and Fifth Third will now have some locations that overlap, which could result in some branch closures.

As part of the transaction, M & I is buying $300 million in Fifth Third loans and $450 million in deposits.

With the purchase, M & I with have 25 branches, $1.3 billion in deposits and $1.4 billion in assets, making it solidly the sixth largest bank in the state. The deal also diversifies M & I geographically in the state, with new branches in Prescott, Sedona and Green Valley--all northern Arizona towns. The deal will also give M & I a more significant presence in the state's mortgage landing arena.