An 18-year-old woman killed by a car that barrelled down a pavement in New York's Times Square was a tourist, police said.
Alyssa Elsman, from Portage, Michigan, died and 23 people were struck by the car before it was stopped by a security barrier. Police said the woman's 13-year-old sister was among the injured.
The driver, a 26-year-old US Navy veteran, told officers he was hearing voices and expected to die, two police officials said.
Helpless pedestrians had little time to react as the car went the wrong way up the pavement before smashing into a row of steel security barriers installed in recent years to prevent vehicle attacks on the square. The car came to rest with its two right wheels in the air.
"He didn't stop," said Asa Lowe, of Brooklyn, who was standing outside a store when he heard screaming as people scattered. "He just kept going."
The carnage raised immediate fears of terrorism, fuddled by recent attacks in England, France and Germany in which vehicles ploughed through crowds of pedestrians. But investigators quickly turned their focus to the sobriety and mental health of the driver, identified as Bronx resident Richard Rojas.
"There is no indication that this was an act of terrorism," Mayor Bill de Blasio said.
Photographers snapped pictures of Rojas after he climbed from the wrecked car and ran through the street before he was tackled by a group that included a ticket seller and a muscular door supervisor at a nearby Planet Hollywood restaurant.
Rojas initially tested negative for alcohol, but more detailed testing was being carried out, according to two police officials.
The officials said Rojas told officers he had been hearing voices.
A week ago, Rojas was arrested and charged with pointing a knife at a notary, whom he accused of stealing his identity. He pleaded guilty to a harassment violation.
He was arrested on charges of driving while intoxicated in 2008 and 2015, police Commissioner James O'Neill said. He pleaded guilty to an infraction in 2015 and was ordered to complete a drunken-driving programme and lost his licence for 90 days.
In previous arrests, he told authorities he believed he was being harassed and followed, one of the police officials said.
Ms Elsman graduated last year from Portage Central High School.
"If you didn't know her, you might think she's reserved or shy," school principal Eric Alburtus said. "But if you could talk to her for a minute, you'd realise she was engaging. She was bright. She was funny."
In the Bronx, neighbourhood acquaintances said Rojas was a friendly man who had been having problems. Harrison Ramos said Rojas was not the same when he came back from active duty in 2014.
"He's been going through a real tough time," he said.
Rojas enlisted in the Navy in 2011 and was an electrician's mate fireman apprentice. In 2012 he served aboard the USS Carney, a destroyer.
Navy records show that in 2013 he spent two months at a naval brig in Charleston, South Carolina. They do not indicate why.
Rojas was based at the Naval Air Station in Jacksonville, Florida, before being discharged in 2014 as the result of a special court martial, a Navy official said. Details were not immediately available.