Miguel A. Reyes-Pantoja, 26, of 23 Poningo St., Port Chester, was arrested at the scene on South Water Street by Greenwich Police.
Fellow taxi drivers had rushed to the area after the victim called for help over the taxi's CB radio, and they notified police.
Reyes-Pantoja was charged with first-degree robbery, first-degree assault and breach of peace.
He was accused of grabbing the driver by the neck at about 3:15 a.m. and demanding his wallet. police said. He also cut the driver's neck and face, causing severe life-threatening injuries, police said.
The taxi driver was rescued after he made the desperate call over the CB radio, police said. He was taken to the Stamford Hospital, where he was immediately taken into surgery.
Reyes-Pantoja was held on $500,000 bond. His first scheduled court date is Feb. 23 in state Superior Court in Stamford.
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