A Teamsters security guard working on TNT‘s “Falling Skies” in Vancouver was killed by an unattended truck Monday night on the set, Variety has confirmed.

The accident, which happened in Vancouver suburb Burnaby, took place while production was preparing for the next day’s shoot. According to reports, Scott McCloy, a spokesperson for British Columbia’s Workers’ Compensation Board WorkSafeBC, said the security guard was standing near a 5-ton truck, which was left unattended. The truck slide down a slope and fatally pinned the security guard to a tree.

“Last night, a security guard working on the set of TNT’s ‘Falling Skies’ was fatally injured while the production was preparing for the next day’s shoot,” TNT said in a statement. “The accident is currently being investigated. We are deeply saddened by this tragic event, and on behalf of the producers and TNT, we wish to express our heartfelt condolences to the family of the security guard.”

The security guard was part of Vancouver Teamsters Local 155 and his name has not been made public. Production has halted since the accident.

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