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FBI strains to keep up with investigations

From NBC's Pete Williams

FBI Director Robert Mueller told Congress today that the bureau is struggling to keep up with an explosion of investigations into corruption by public officials and mortgage fraud.

He told a Senate committee today that the FBI has a surprising 2,500 public corruption investigations open now -- up nearly 60 percent since 2003. In just the past two years, FBI investigations have brought about more than 1,600 convictions of federal, state and local public officials. 

Mueller said the FBI's mortgage fraud load has more than doubled in the past three years, to more than 2,000 cases from 700. The FBI has more than 566 open corporate fraud investigations, including some directly related to the current financial crisis, he said.

But Mueller said these cases are putting a strain on the FBI, which has been forced to shift resources from other criminal investigations. The number of agents investigating mortgage fraud has risen from 120 to 250 in the past two years. And it's clear that will have to grow more. Since last fall, nearly 29,000 reports of potential fraud have been filed, he said.