I think the bank is stealing my grandmother's estate.

Hello, I am the trustee of my Grandmothers estate. The bank she had designated to watch over her estate took complete possession of all of her assets very soon after her death. The bank is now selling off all of the homes my grandmother worked her entire life for at the lowest point in the market in years. They plan on selling all of her assets and using the money to put into C.D. accounts. I know this would make my grandmother sick; she worked two or more jobs for most her life and took care of handicapped kids for years to buy an even amount of homes so that my brother and I would have an equal number of homes when we inherited them at the age of 40. The first portfolio summary I received from the bank was valued over $600,000 USD in September of 2009. The latest portfolio summary dated 6-30-10 value is barely $300,000 USD. The bank will not provide me with the information or documents of where the money has gone. This honestly makes me sick to my stomach and I know this is not what my grandmother wanted. IS THERE ANYTHING I CAN DO? If for some reason the bank did not want to be the administrator of the trust the responsibility would be passed to my father who shares an equal respect and appreciation of the value of my grandmothers estate. Any suggestions would be greatly appreciated. Thank you for your time. Seth