The man who was shoved to his death in front of a subway train Thursday night was a 46-year-old from India who lived in New York City and worked for a printing business, police said.
Investigators on Friday searched for an unidentified woman who rose from a bench and suddenly pushed the man from behind, sending him flying onto the tracks as a train entered a station in the borough of Queens.
Police released surveillance video of the woman fleeing the area and have been interviewing witnesses, including some who said she was mumbling to herself before the attack.
The man, who lived in Queens, didn't appear to see the woman coming and was pinned beneath the train as it pulled to a stop, police said. Authorities delayed releasing his name while they worked to notify relatives.
Commuters, meanwhile, absorbed the news of the second fatal subway shove in the city this month.
"It's just a really sad commentary on the world and on human beings, period," said Howard Roth, who takes the subway daily. He said the deadly push made him think about subway safety, "but I guess the best thing is what they tell you _ don't stand near the edge and keep your eyes open."
The woman was described as heavyset and in her 20s. It was unclear whether she and the man knew each other, or whether the attack was simply the act of a deranged stranger.
Asked about the episode at the station on Queens Boulevard in the Sunnyside neighborhood, Mayor Michael Bloomberg pointed Friday to legal and policy changes that led to the release of many mentally ill people from psychiatric institutions from the 1960s through 1990s.
"The courts or the law have changed and said, no, you can't do that unless they're a danger to society; our laws protect you. That's fair enough," Bloomberg said on "The John Gambling Show with Mayor Mike" on WOR-AM.
There are no barriers separating the trains from the people on New York City's subway platforms, and many people fall or jump to their deaths in front of rushing trains each year.
Though shoving deaths are rare, Thursday night's killing was the second one this month. On Dec. 3, a 58-year-old man was pushed in front of a train in Times Square. A homeless man was charged with murder and is awaiting trial.
Other high-profile cases including the 1999 slaying of Kendra Webdale, an aspiring screenwriter, by a former psychiatric patient. That case led to a state law allowing for more supervision of mentally ill people living outside institutions.
Associated Press Writer Jennifer Peltz contributed to this report.