The Kingdom of Wakanda was listed as a free-trade partner of the United States by the U.S. Department of Agriculture, even though it is a fictional country, according to BBC News.

It was included in the department’s online tariff tracker, which listed goods the two countries supposedly traded, including ducks, donkeys and cows, the news outlet reported.

A USDA spokesperson said Wakanda was placed on the list my mistake during a staff test. Wakanda is the fictional East African home country of superhero Black Panther in the Marvel universe — not a real-life trading partner of the U.S.

Francis Tseng, a New York-based software engineer, discovered the listing, BBC News reported, when he was looking up agricultural tariffs as he applied for a fellowship.

Tseng told NPR he was “very confused” when he saw Wakanda on the list, saying, "[I] thought I misremembered the country from the movie and got it confused with something else."

“The fictional country was removed soon from the list after US media first queried it,” BBC News reported, “prompting jokes that the countries had started a trade war.”

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