Authorities at the Ezeiza airport near Buenos Aires discovered the skull wrapped in a towel and a plastic bag in his suitcase, the Diario Veloz newspaper from Argentina reported over the weekend.
The newspaper said the tourist thought the skull, found in the Recoleta cemetery, would make an original souvenir to show to friends back in Switzerland.
However, the teenager is not able to return home for the moment while he faces a provisional charge of theft.
He was about to board a plane to head back to Switzerland when authorities announced on a public address system that there was a “problem” with his baggage.
An x-ray of his suitcase had highlighted the skull, Diario Veloz said.
The young man was questioned via a translator, the newspaper said.
He offered to show investigators the exact place where he found the skull in a cemetery that is known locally as a place for burying famous people, including Evita Perón, the celebrated First Lady of Argentina from 1946 to 1952.
Military generals, presidents, scientists, poets and other luminaries are buried in the cemetery.
The Swiss federal department of foreign affairs has been informed of the Swiss tourist’s situation, according to an online report from the Blick newspaper on Monday.
However, the department was not commenting on the case for privacy reasons.