The incident happened around 10 a.m. on First Avenue near East 37th Street.
Authorities say the 49-year-old driver was in the northbound lanes when he reversed and struck three pedestrians waiting to cross First Avenue.
He reportedly has a reverse camera but apparently did not see anyone behind him while trying to move further from the curb. The incident was caught on surveillance camera.
"They had the right of way to go, but there was a...postal truck that was backing up, and it actually hit them," witness Luis Reyes said. "And I'm yelling, telling him, 'Whoa, whoa, whoa, whoa, watch your back.' And he just kept going back. I think he didn't see them."
A 48-year-old woman suffered a right leg injury, while a 68-year-old woman had injuries to the leg, arm, ribs and neck and her 66-year-old husband suffered injuries to both legs.
"I saw him just mow them down," Reyes said. "He just kept going, but he couldn't see them."
Reyes ran across the street to help after the accident, almost getting hit by a car himself.
"I got over there, and the guy was screaming, the lady was crying, she was under the truck," he said. "I just called for help, and my partner came and some good people that were there actually helped us move the truck a little forward...I actually took my jacket and put it under his head. I thought they were dead, to be honest with you."
All three victims were taken to Bellevue Hospital in stable condition and are expected to survive.
The driver, from Queens, was charged with failure to yield.
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