By Chris Nashawaty
October 11, 2011 at 07:25 PM EDT

An accident on the Toronto set of Resident Evil: Retribution early Tuesday morning has injured several background actors and sent 11 of them to the hospital, sparking an investigation by the Ontario Ministry of Labour. The mishap occurred at  Toronto’s Cinespace Film Studios facility at 8:35 a.m., and involved a four-foot high platform shifting position, leaving a gap into which the actors fell. Since the actors were reportedly dressed as zombies, paramedics could not tell at first which of them were actually injured or merely in character.

According to the film’s unit publicist, Karen Pidgurski, none of the injuries were life-threatening. One background actor suffered a cracked rib, one a stress fracture of the tibia and one a possible back injury. Seven of the 11 hospitalized actors have already returned to the set. The movie franchise’s star, Milla Jovovich, was reportedly not on the set at the time of the accident.

The film’s production company released a statement saying: “It is with regret that we confirm this unfortunate accident. The thoughts of everyone involved in the production are with those who have been injured, and we hope that all have a quick and complete recovery. The filmmakers are continuing to work closely with the authorities in responding to this incident.”

According to a Labour Ministry spokesman, the investigation has no plan at the moment to shut down production on the Screen Gems picture.

Resident Evil: Retribution is the fifth chapter in the popular video-game-turned-action-movie franchise.

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