Police say a gunman took several hostages during a failed robbery at a Tucson bank Monday, then killed himself as authorities surrounded the building.

Police spokesman Sgt. Mark Robinson says no hostages appear to have been injured.

Robinson says the unidentified robber took money from a teller early Monday afternoon.

Police say the man was leaving but ran back into the bank after seeing an investigator for the county prosecutor's office who was coming in to do some banking.

Robinson says the man briefly took several people hostage and had released all but some bank employees when he killed himself.