The incident happened while festival jury members Christoph Waltz and Daniel Auteuil were being interviewed for the live television broadcast of "Le Grand Journal," a nightly news and entertainment program.
Waltz and Auteuil were briefly rushed offstage as a precaution, but the program resumed after police escorted the man out.
The man reportedly fired two blanks from a gun and had been holding something resembling a grenade at the time he was apprehended, The Hollywood Reporter said.
No injuries were reported.
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