The actress had an outburst during the shooting of No One Killed Jessica, The Times of India has reported.
She told the paper: "Yes, it happened a few days ago, and it scared the hell out of me and everyone in the unit.
"I don't know what happened to me. I just broke down. It was work pressure. In the past three months I didn't have a day's respite. It was crazy."
It was recently reported that Balan fell out with No One Killed Jessica co-star Rani Mukherjee on set.
