These "ultra thin" pads were thick with cash.

U.S. Customs and Border Protection officers at Detroit Metropolitan Airport discovered more than $60,000 in cash hidden inside a package of menstrual pads in a passenger’s baggage on Feb. 3.

The undeclared currency was bundled inside envelopes concealed inside the package, CBP officers said. The woman had told officers that she was only carrying $1,000.

U.S. Customs and Border Protection officers at Detroit Metropolitan Airport discovered more than $60,000 in cash hidden inside a package of menstrual pads in a passenger’s baggage on Feb. 3. (U.S. Customs and Border Protection)

The passenger had been headed to Amsterdam when the hidden money was discovered.

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The officers seized the money because the woman violated currency reporting requirements, officials said. U.S. law requires anyone transporting more than $10,000 into or out of the country to report it to a CBP officer. Anyone who doesn’t report the currency faces civil fines or seizure of the money.

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Robert Larkin, port director, said CBP enforces the currency reporting rules in order to combat money laundering and other criminal schemes.

"I’m proud of our officers and the work they do to interrupt currency smuggling operations and illegal activities daily," Larkin said.

The passenger at Detroit Metropolitan Airport had been headed to Amsterdam when the hidden money was discovered. (iStock)

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CBP officers seized more than $93.3 million in currency in 2020, according to the agency.