NEW YORK -- Stocks plummeted more than 500 points at one point Monday afternoon because of what some are calling the biggest financial crisis in years.

Lehman Brothers filed for the biggest bankruptcy in history.

The troubled investment bank was hoping for bail out, but that was dashed late Sunday night when a potential buyer withdrew their offer.

Meanwhile, Bank of America Corporation agrees to buy Merrill Lynch for $50 billion in stock.

Bank of America has the most deposits of any U.S. bank, while Merrill Lynch is the world's largest and most widely recognized brokerage.

Bank of America said the deal is the opportunity of a lifetime.

"We can do so much more for our clients, both on the retail side and the corporate banking side with the capabilities Merrill Lynch brings for us and we always say as we take care of customers they'll take care of our shareholders," said Ken Lewis from Bank of America.

Bank of America said its buyout is expected to close in the first quarter of 2009.

Meanwhile, oil prices closed below $100 a barrel for the first time since early March, settling down $5.47 to $95.71.

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