The stunt men were shooting a car chase sequence for the film in Chicago when the accident happened, The Times of India reports.
A source described the scene, saying: "The car was speeding and the driver must have lost control. It rammed into the pavement. Because of the momentum, the glass shattered and the people inside got injured badly."
Aamir Khan, who plays a negative role in the film, was said to be shocked by the incident in which his own stunt double was injured.
"Aamir Khan was a part of the chase sequence," the source added. "When the accident happened, he was so shocked that he couldn't react for a little while. Uday Chopra, who is always there on the sets, rushed to help the men out of the broken car."
An official spokesperson from Yash Raj confirmed that, while the stunt men were injured, they are now fully recovered and have returned to work on the film.
Khan and Katrina Kaif have been training extensively for the film's elaborate stunt sequences.