About three months before former auto titan Carlos Ghosn’s escape last week from Japan to Lebanon, an operative helping plan his extraction visited Kansai International Airport in Osaka, Japan, and realized there was a huge security hole, according to a person familiar with the matter.

The terminal for private jets was quieter than those at most other airports and essentially empty, unless there was a flight coming in, this person said. What’s more, oversize luggage was too big to fit in the airport scanners.

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