The 75-by-75-foot section toppled above a rear loading dock at the Brae Boulevard building after a frozen water pipe burst around 6 p.m., they said. No injuries were reported, and damage apparently was limited to the truck.
Borough police and firefighters responded, along with the Hackensack Fire Department, while an ambulance as put on standby but wasn't required, responders said.
The sprinkler system was shut down and the building evacuated, they said.
The owner was on scene, with hopes that the building could be reopened Wednesday.
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