Nine people have been killed after a helicopter carrying tourists and a light aircraft collided near New York City and crashed into the Hudson River.
The collision occurred between Hoboken, in New Jersey, and Manhattan, just across the river, on Saturday.
Mayor Michael Bloomberg said six people - one pilot and five Italian tourists - were on the helicopter. Three people including a child were on the plane.
Three bodies have been found and divers were returning to the area on Sunday.
Mr Bloomberg said on Saturday that the emergency operation had changed from a rescue to a recovery mission and that the incident was "not going to have a happy ending".
He said it appeared the plane had flown into the rear of the helicopter, but stressed that an investigation needed to be carried out.
He said rescue workers had located some wreckage, probably of the helicopter, but that due to the limited visibility 30ft under the water it had not been possible to confirm which of the aircraft it was.
National Transportation Safety Board Chairman Debbie Hersman said that a helicopter pilot on the ground had seen the plane approaching the helicopter.
"He radioed the accident helicopter and told him: 'One-lima-hotel. You have a fixed-wing behind you.' There was no response from the pilot," she said.
The pilot on the ground then saw the plane's right wing strike the helicopter and both aircraft "descended into the Hudson River", she added.
Television footage showed rescue craft heading to the site, about level with Manhattan's West 14th Street, from both sides of the Hudson River after the incident happened.
"We heard first a huge crash, a boom almost," said Melissa Green, who was having lunch on the New York bank of the river at the time.
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