The 31-year-old man landed on a BMW sedan after jumping from a building at the intersection of Sip Avenue and Enos Place at 26 Journal Square around 10:30 a.m., city spokeswoman Kimberly Wallace-Scalcione said.
The man's injuries were considered life-threatening, she said.
Witnesses at the scene rushed over and called 911.
Among them Christina Smith, who captured the aftermath on video.
"The sound was very loud," she said. "He was screaming 'help.'
"I was trying to tell him to calm down and stop moving."
Video from the scene shows the man trying to stand up, while civilians urge him to stay still and calm until help arrives.
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