At least 10% of the $360 billion Congress provided for unemployment benefits in the Cares Act has been distributed improperly, mostly due to fraud, according to a preliminary analysis by the Office of the Inspector General for the Department of Labor.

“This is the largest fraud attack on the U.S. ever. Period,” Blake Hall of ID.me, which provides identity-verification to state unemployment agencies, told CNBC. “And it’s not even close.”

Most of the fraud is concentrated in the Pandemic Unemployment Assistance program, a temporary effort to help people who are usually ineligible for benefits, including contractors and the self-employed. More than 8 million people were receiving benefits through the PUA program in December.

In some states, more than 35% of applications for PUA were fraudulent, with most involving identity theft. Organized crime has been involved, including criminal groups in China, Nigeria and Russia, CNBC’s Greg Iacurci reported.

The new $900 billion Covid relief bill includes another $120 billion for the unemployed, as well as more stringent requirements for aid recipients, including documentation of employment. But those new rules could make it harder to distribute benefits quickly, delaying payments by weeks or months.

“It’s a little bit of a high wire act because there’s so much pressure to get money out,” Bill McCamley, cabinet secretary of the New Mexico Department of Workforce Solutions, told CNBC.

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