New York Police Commissioner Raymond Kelly said Sian Green, the British woman who had part of her leg severed in a collision involving a taxi in Manhattan, remains sedated in hospital.
Police said the taxi driver had been issued with a summons for being an unauthorised driver of the car.
Mr Kelly said the incident remains under investigation and the driver could face other charges.
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Mixed fortunes across the UK tomorrow. Still breezy across the north.
The Labour leader said socialist politics would not be put "back in a box" as he appeared on stage at the festival.
There are reports that at least some MPs and Lords have been left unable to access their emails as a result of the attack.