SAN FRANCISCO (KPIX 5) — A strong gust of wind knocked over construction fencing in San Francisco’s Mission District Sunday afternoon, injuring two people including a man who is in critical condition.

The two people were walking by the construction site at the intersection of 23rd Street and San Jose Avenue in the Mission Sunday afternoon when the wind knocked over the fencing.

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The injuries were reported at 2:54 p.m.

“A gust of wind came and the whole fence started to wave. The back end of the fence was basically some plywood and two people actually got squished underneath it,” said witness Julian Stein.

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Stein said a big piece of plywood hit a man and a woman as they walked down the sidewalk. Both were hurt.

Local resident Angie Avila took video from across the street after the accident happened that showed the man on the ground being helped by police. She said the man was injured more seriously.

Fire officials confirmed that one of the pedestrians suffered life-threatening injuries.

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“He didn’t even know that he was even injured in the back of the head. He was trying to get up. I told him to sit down and to wait, not to get up,” said Stein. “He put his hand on the back of his head and said, ‘What? I didn’t even notice that I was bleeding. And then he started kind of freaking out a little bit.”