WASHINGTON -- A top Pentagon auditor told Congress on Thursday that $10 billion in defense contracts for Iraq reconstruction and troop support were either excessive or undocumented, including $2.7 billion for contracts held by Halliburton or one of its subsidiaries.

William Reed, director of the Defense Department's Defense Contract Audit Agency, told the House Oversight and Government Reform committee that his agency discovered the problems --$4.9 billion in "questioned" or overly expensive charges, and $5.1 billion in "unsupported" or undocumented expenses-- after auditing $57 billion in Pentagon contracts.

Reed acknowledged that worn-torn Iraq lacked ideal circumstances for solid accounting practices, but said that his organization required some form of evidence to support costs.

Rep. Henry Waxman, D-Calif., chairman of the committee, said further audits may uncover more questionable spending.

"American taxpayers have already spent over $350 billion for the war in Iraq. There's $300 billion still to audit. The total amount of waste, fraud and abuse could be astronomical," Waxman said.

The new audit report put the spotlight again on Halliburton, the Houston-based conglomerate formerly headed by Vice President Dick Cheney, which has landed large Pentagon contracts without competition.

Most of Halliburton's $2.7 billion in questionable charges came from programs to feed and support U.S. troops.

The auditors reported that a Halliburton subsidiary, KBR, overcharged the Pentagon by $212 million for meals served to U.S. troops in Iraq, $100 million for troop housing sites that had already been shut down and $42 million in subcontractor costs that were duplicated.

The rest of Halliburton's questionable costs came from contracts to rebuild oil fields, according to the audit report.

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