Federal agents at the Philadelphia International Airport Sunday seized nearly $27,000 from a Ghana couple after the duo allegedly failed to report the cash.

Investigators said the couple was after their arrival from Germany referred to a secondary inspection during which the man said he had $6,000. When U.S. Customs and Border Protections officers explained federal currency reporting requirements, the man revised his estimate and wrote he had $16,000, according to authorities.

A baggage examination allegedly turned up multiple envelopes containing $27,431.30 in U.S. currency, British pounds, Swiss francs and Ghana cedi. Officers returned $500 to the couple for "humanitarian purposes," according to a news release, and seized the remaining $26,931.30.

The couple was then released. No criminal charges were filed.

Though there is no limit on how much currency travelers can bring into or take out of the U.S., they are required to formally report amounts of $10,000 or more.

"CBP derives no great pleasure from seizing travelers' currency," acting CBP port director for the area port of Philadelphia Tarance Drafts said in a statement. "However, there are consequences for failing to comply with U.S. currency reporting laws."

The U.S. Customs and Border Protection collects over $30 billion annually, making it the second largest revenue generator for the nation's government, according to a release. Officers conduct regular inspections of international passengers and cargo to search for terrorist weapons, narcotics, counterfeit merchandise, banned agriculture and unreported currency.