Christoph Waltz was left shaken after his television interview was interrupted by gunfire.
The Django Unchained actor was being interviewed for France's Le Grand Journal at the Cannes Film Festival when gunfire was heard and he was quickly rushed to safety.
He told the Daily Mail: "I was on a panel at the Studio Canal platform off the beach when a man produced a gun. I think it was a pistol and he fired but luckily for me they were blanks.
"Then he shouted he had a grenade and again luckily for me there was no grenade.
"The police have him. They tackled him to the ground. I don't know who he was or where he came from or what his problem was."
The man was arrested at the scene and police found he was carrying a fake grenade and a knife.
A police source said: "It really appears to be a crazy guy."
No injuries were reported and the telecast resumed a few minutes later.
Actress Robin Wright revealed she heard the commotion but was unsure of what had happened.
She said: "I saw ambulances and police but I didn't know what they were for. It held traffic up but I didn't know the details till I heard it from Christoph."
- BANG! Showbiz