A private helicopter crashed into New York City's East River shortly after takeoff this afternoon. Divers found the body of a female passenger about 90 minutes later.

Update at 7:10 p.m. ET: Authorities have identified the dead woman as Sonia Marra Nicholson, a Briton living in Australian who was visiting New York to celebrate her 40th birthday, ABC News says.

The other three passengers were Nicholson's partner, Helen Tamaski, along with Nicholson's mother, Harriet, and stepfather, Paul.

Tamaski is in critical condition. Nicholson's parents, who live in Portugal, were listed in stable condition at separate hospitals.

Update at 5 p.m. ET: A city official says the female passenger was found underwater about an hour and a half after the crash and was dead, The New York Times reports.

Update at 4:48 p.m. ET: The missing passenger, a woman, has been accounted for, Fox TV reports.

Her condition has not yet been announced.

Update at 4:45 p.m. ET: Witnesses described hearing and seeing the helicopter sputter and fall.

Joy Garnett told the Associated Press that she and her husband were on the dock waiting to take the East River ferry to Brooklyn when they heard the blades of a helicopter and saw it start to take off from the nearby helipad. She said she saw it do "a funny curlicue."

"I thought, `Is that some daredevil move?'" she said. "But it was obviously out of control. The body spun around at least two or three times, and then it went down." She said the chopper had lifted about 25 feet off the ground before it dropped into the water without much of a splash. It flipped over, and the blades were sticking up out of the river. She said people on the dock started throwing in life jackets and buoys. Two people came up out of the waves. "It didn't make much noise," she said. "It was just a splash and sunk."

Update at 4:24 p.m. ET: Hypothermia is not a concern; the water temperature is about 67 degrees Fahrenheit, the National Weather Service reports.

Update at 4:21 p.m. ET: NYPD reports that the helicopter developed some kind of problem and was attempting to return to the 34th Street helipad shortly after taking off but crashed into the water.

CBS New York reports that two female passengers were taken to Bellevue Hospital -- one was in cardiac arrest and the other in respiratory arrest. A man was taken to a nearby hospital.

Update at 4:12 p.m. ET: Various, and conflicting, reports say the helicopter was private, commercial or tourist.

The New York Post reports, without attribution, that two people were pulled out in serious condition and taken to Bellevue Hospital, and that the helicopter sank to the bottom upside down within minutes after the 3:24 p.m. crash.

Initial reports also say the helicopter crashed just after taking off from the 34th Street helipad, but CBS New York, citing the NYPD, reports that the helicopter crashed as it attempted to land at the helipad.

Update at 4:02 p.m. ET: The helicopter went into the river off 34th Street. Here's a live stream.

Update at 3:58 p.m. ET: AP says four people -- the pilot and three passengers -- have been rescued, according to NYPD. A fifth person remains missing and the helicopter, a Bell 206, is fully submerged.

Original post: A private helicopter carrying several people has crashed into the East River in New York City shortly after takeoff, according to news reports.

Three people reportedly have been rescued. ABC News says a fourth person could be seen being pulled from the water onto a raft and appeared to be unresponsive. The location of the fifth person was not yet known.

The crash happened about 3:15 p.m. ET.