Federal investigators pursuing evidence of bid rigging, bribery, and kickbacks in Pentagon procurement are reviewing $6 billion worth of contracts to provide essential supplies to American troops in the Middle East, the New York Times reported on Friday.

That's double the $3 billion in contracts to provide essential supplies to American troops in Kuwait, Iraq, and Afghanistan—including food, water, and shelter—that the Pentagon had previously acknowledged were under review.

Military officials said that an additional $88 billion in programs, including those for body armor for American soldiers and matériel for Iraqi and Afghan security forces, is being audited for "financial irregularities."

The potentially large-scale instances of corruption have come to light as part of a growing government investigation into widespread corruption in the Pentagon's war-procurement system.

The New York Times said that at a hearing before the House Armed Services Committee, a panel of high-ranking Defense Department officials alleged that the Pentagon was not doing enough to provide both training and oversight of officers involved in defense contracting.

Harsh criticism came from both sides of the aisle, as these charges are coming to light more than two years after Congress passed legislation to help the Pentagon correct serious problems in its purchasing system.

Pentagon officials did not dispute the seriousness of the problems, the New York Times said. However, they questioned whether the wrongdoing represented isolated incidents or a more systematic problem.