A man, 28, and woman, 48, who had just met, were caught committing a sex act in their seats on a Delta flight Sunday from Los Angeles to Detroit, WDIV-TV (Channel 4) reports.
Both were issued citations, and an FBI investigation is underway, the station reports.
FBI spokesman Ray Johnson said in an e-mail to the Free Press that the bureau won't comment on "open or ongoing investigations, but broadly I can say we do investigate crimes aboard aircraft, once the boarding door closes, regardless of severity."
An airport spokeswoman said she's looking into the report, and Delta Air Lines didn't immediately respond to a request for comment.
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