Cruise is famous for doing many of his own stunts. Video from the set shows the actor attempting to jump from one building to another, but falling short and smacking into the side of the second building. The extent of his injuries are unknown, but a source told Variety that the actor may have broken his ankle and hurt his hip.
A doctor is reportedly to examine Cruise this week, after which Paramount will decide how long to delay production.
Filming could still wrap on time, if Cruise's scenes are pushed to the tail end of the shoot. But if production does run over schedule, it'll cause major problems for the other cast members, including Henry Cavill, Simon Pegg, and Rebecca Hall, who have other projects waiting for them in the fall.
"Mission: Impossible 6" is due in theaters July 27, 2018.