MILWAUKEE (CBS 58) -- Milwaukee Public Schools (MPS) says the district is out nearly $200,000 after falling victim to bank impersonation fraud.

The school district says initially $450,000 was lost, but MPS has managed to recover $255,000. It's now working with US Bank to get the remaining $195,000 back.

MPS has not explained how it happened. 

Superintendent Brenda Cassellius says the district is tightening its financial safeguards. 

MPS says state and federal authorities, including the FBI and Milwaukee Police Department, have been notified. 

The district is also conducting its own internal investigation.