Crews were filming a sequel to "Resident Evil" in Toronto Tuesday when a platform collapsed, injuring 16 actors.
Many of the wounded were dressed as blood-covered zombies, making it tough for first responders to figure out who was hurt and who was just in makeup.
The victims fell about 20 feet. Many of them suffered leg and back injuries, but none of those injuries were life-threatening.
The film's producers, Davis Films/Impact Pictures (RE5) Inc., Constantin Film International GmbH, issued a statement that said the accident involved background actors. They said a 4-foot high platform separated from the set, creating a gap.
"Resident Evil: Retribution" is the fifth installment of a franchise based on the popular video game series and will be distributed by Screen Gems and Sony Pictures.
The film's star, Milla Jovovich, was not on the set.
The Associated Press contributed to this report.