The aircraft is believed to have been approaching Buffalo Niagara International airport amid sleet, snow and fog when it came down on a suburban street at around 10:10pm (0310 GMT).
A county official said "the plane simply dropped off the radar screen".
Alison Des Forges, a prominent writer and human rights expert on Rwanda, was among those killed, David Patterson, the New York governor, said.
Barack Obama, the US president, said he offered his "thoughts and prayers" to those affected by the "terrible tragedy".
Witnesses revealed their horror as the jet descended over the neighbourhood before crashing into a house, killing one of the inhabitants.
"We heard a very low humming sound, like a buzz. It was something I have never heard before. Then there was dead silence," a local resident told Fox News.
"After that dead silence, the whole building shook. At that point, you heard a terrifying boom, like a crash."
"It was terrifying. [And] when you got to the scene, [the fire] was so intense that there was no hope. You knew that there were not going to be any survivors."
It also emerged that one of those killed in the crash, Beverly Eckert, had lost her husband in the September 11 attacks in New York City in 2001.
The crash was the first fatal of a commercial airliner in the United States since August 27, 2006, when 49 people were killed after a Comair jetliner mistakenly took off from a Lexington, Kentucky, runway that was too short