The search for nine people aboard a small plane and a helicopter that collided Saturday over the Hudson River has become a recovery mission, New York Mayor Michael Bloomberg said.
First responders gather on a pier after a plane and helicopter collided Saturday over the Hudson River.

Two bodies have been recovered, but it was unclear whether the second was from the crash, which authorities "do not feel was survivable."

Two passengers, including a child, and a pilot were believed to have been aboard the single-engine Piper PA-32 when it collided with the copter around noon between New York and Hoboken, New Jersey, Bloomberg said.

Five Italian tourists and a pilot were believed to be aboard the helicopter, an American Eurocopter AS350 operated by Liberty Helicopter Sightseeing Tours, Bloomberg said. See witness photos

Relatives of the victims were receiving counseling, he said.

At least one piece of wreckage was found, but the murky waters of the Hudson, where underwater visibility is about two feet, hampered divers' efforts, Bloomberg said.

Preliminary reports indicated the airplane ran into the back of the helicopter, Bloomberg said, but warned that no official information was yet available. Police search for debris

"Until the National Transportation Safety Board makes its determination, nothing is a fact," he said.

Earlier, the Coast Guard reported it had rescued one person from the river.

Witness Arnold Stevens said after the plane had a wing sheared off, it began "corkscrewing" into the water. The helicopter "dropped like a rock" after the collision, which happened about noon. Video See a series of photos from the scene

A small plane landed at Teterboro to pick up one passenger late Saturday morning and took off at 11:54 a.m., said Ron Marsico, spokesman for the Port Authority of New York and New Jersey.

The travelers filled out a flight plan indicating they were flying from Teterboro Airport in New Jersey to Ocean City, New Jersey, the FAA said.

Radar contact was lost with a small plane this morning that is believed to be the aircraft involved in the crash, FAA spokeswoman Arlene Salac said.

Ben Berman, formerly with the National Transportation Safety Board, which will investigate the accident, said if the helicopter fell straight down, it's likely there was a rotor failure. Were you there? Send images

Witnesses reported seeing debris flying from the helicopter as it crashed.

Scott Schuman was with his grandparents on the Hoboken side of the river when they heard a loud bang.

"The plane was kind of whirlybirding its way down, brown smoke coming out the back of it, and it crashed into the water. Then a few seconds later the helicopter with debris falling off of it also hit as well," Schuman said.

"It was a scary sight," he added.

He said some of the debris fell in Hoboken, and "we covered our heads."

Asked if he had seen anyone in the water, Schuman replied, "I have not seen anything, but judging by the impact when the plane and the helicopter hit, it would be very unlikely for a positive outcome."

The busy airspace surrounding New York's Manhattan island has been the site of several aeronautical mishaps in recent history.

Earlier this year, a US Airways plane with 155 people on board ditched into the Hudson, apparently after striking at least one bird upon takeoff from New York's LaGuardia Airport, officials said.

Capt. Chesley B. "Sully" Sullenberger's landing, which resulted in no deaths or serious injuries, was captured on closed circuit television.

In 2005, Yankees pitcher Cory Lidle and his flight instructor were killed when the 34-year-old ballplayer's plane crashed into a high-rise apartment building near the East River, city officials said.

New York mayor: Aircraft collision over Hudson not 'surviveable' -

CNN's Susan Candiotti contributed to this report.