5:46 - According to the Times, the authorities identified the pilot, Paul Dudley, as the director of Linden Airport in New Jersey. The paper says Dudley was the pilot of a Cessna light plane that made an emergency landing in a Brooklyn park in 2006.
5:00 - The Times, citing a city official, reports that the missing woman, who was found underwater by police divers 10 minutes ago, is dead. WNBC is reporting that the passengers were tourists from England, though there are conflicting reports about their identities.
4:52 - CBS New York is reporting that the fifth passenger, a woman, has been recovered but there is no word yet on her condition.
4:44 - The owner and pilot of the chopper has been identified as Paul Dudley, according to the New York Post. Local TV stations are playing video of him doing a frantic backstroke away from the wreckage (it appears the helicopter wasn't equipped with flotation devices):
4:32 - There's some confusion about whether the helicopter was taking off (as reported by the AP below) or landing before it crashed. A witness tells the Times that he thinks the helicopter was blocked from landing on the helipad by a second helicopter, prompting the chopper to spin around and then fall into the water.
4:27 - With one passenger still unaccounted for, The New York Times, which has set up a live blog, is reporting that two injured women were taken to Bellevue Hospital Center, with one in cardiac arrest and another in respiratory arrest. A man in "serious condition" has been taken to the New York University Langone Medical Center while the pilot, also male, is conscious and receiving treatment at the location of the crash.
Original Post (3:57 pm) - A helicopter carrying at least five people crashed into the the East River in New York City just before 3:30 pm near 34th Street, sinking within minutes, according to the New York Post. The AP reports that FDNY firefighters and NYPD rescuers have pulled the pilot and three others from the water thus far, and rescue efforts are continuing. The AP adds that the commercial Bell 206 chopper had just taken off from a heliport before it crashed. We'll update when we learn more about the incident, but for now, the images on television of survivors clinging to the wreckage and the massive rescue effort, shown above and below, are riveting the city.
Here's a live feed from CBS New York: