A U.S. Navy veteran plowed his auto into pedestrians in New York City's packed Times Square, killing an 18-year-old woman and injuring 22 people.
Rojas' motivation was unclear, but Democratic Mayor Bill de Blasio said there was "no indication that this was an act of terrorism".
Numerous victims were carted off on stretchers and four people were in critical condition but likely to survive, FDNY Commissioner Daniel Nigro said.
The driver, Richard Rohas, 26, of the Bronx, was taken into custody at the scene, New York Police Commissioner James O'Neill said at news conference about 90 minutes after the incident.
Rojas, 26, is a Bronx resident, US citizen and Navy veteran, the mayor said. They said he had been arrested twice for drunken driving in 2008 and 2015, and once earlier this month for menacing.
Rojas initially tested negative for alcohol, but more detailed testing was being done to determine if he was high, according to two law enforcement officials who were not authorized to speak publicly and spoke to The Associated Press on the condition of anonymity. Photos from the scene showed multiple victims on the ground near the maroon Honda sedan, which came to rest on two wheels, wedged up against a light pole and 3-feet-tall metal "bollard" barriers.
A auto has ploughed into pedestrians at speed in Times Square, New York.
Elsman's 13-year-old sister was also struck by the auto, but survived, police said. Video posted online showed steam or smoke pouring from the auto for a few moments after it stopped moving.
The young woman is believed to have been visiting NY with her family when the speeding vehicle drove into them and almost two dozen others.
Police and fire officials closed off an area of several blocks.
The crash happened at midday on a hot, clear day that brought large crowds of people into the streets to enjoy the good weather. He turned in time to see the auto roaring up the street. Up to 20 people might be injured and rammed into a crowd of people.
The deadly rampage on Thursday started after the driver allegedly made a U-turn, then steered the vehicle into the packed sidewalk where it rammed dozens of pedestrians for a three block stretch.
Rojas attended college and works in real estate, Ramos said. "We feel deeply for those injured and particularly for the family of the young woman who was lost". Three other people had serious but not critical injuries, and 15 people had less serious injuries, he added.
Video captured by Italian broadcaster Mediaset on Thursday (May 18) shows the moment a vehicle crashed into a crowd in New York's Times Square.
Police are ruling out terrorism and the driver is said to have a history of drink driving. President Donald Trump, whose home at Trump Tower is one mile from the crash scene, was made aware of the incident nearly immediately and given updates, White House Press Secretary Sean Spicer tweeted.
Witnesses described seeing people being loaded on to stretchers, shoes scattered around the scene and people in bloodstained blankets.
"This is a tough day for New York City, but I want to thank our first responders who got here so quickly".
Recent attacks in England, France and Germany in which vehicles ploughed through crowds of pedestrians led to fears this was a terrorist incident. But do you think that, if the suspect said, "Allah made me do it!" this story would have been covered differently no matter what drugs he was on?