(CBS/AP)-- The crash of a volunteer Angel Flight in upstate New York that killed at least two people is under investigation, and the search for the missing pilot is ongoing, authorities said.
Fulton County Sheriff Thomas Lorey said the flight's two passengers were found dead near where the twin-engine plane crashed in a wooded area in Ephratah, about an hour west of Albany. He said the search for the pilot will continue Saturday morning. Officials did not immediately identify the passengers or pilot.
"The bulk of the plane is in the water, in a pond, completely submerged and we have to wait until daylight to put divers in," the sheriff said.
The twin-engine Piper PA 34 departed from Hanscom Field in Bedford, Mass., and was headed to Rome, N.Y., before it crashed just after 5 p.m. Friday, Federal Aviation Administration spokeswoman Kathleen Bergen said.
Angel Flight is a nonprofit group that arranges free air transportation for sick patients from volunteer pilots. Larry Camerlin, president and founder of Angel Flight Northeast, said the organization was "tremendously saddened" by the tragic news of the crash.
"We all offer our thoughts and prayers to the families of those affected," Camerlin said in a statement. "Our volunteer pilots are the most compassionate and generous individuals who donate their time, aircraft and fuel to transport patients and loved ones for free to essential medical care that would otherwise not be readily available to them. There are no words that can adequately express our sorrow."
An employee at an ice cream shop in nearby Johnstown who refused to give her name said she heard what sounded like engine failure and then a loud explosion, "like a gun shot."
She said she went outside and "there were pieces of airplane coming out of the sky."
The FAA and the National Transportation Safety Board will investigate the crash, including what the weather conditions were like at the time of the accident.
At the time of the crash, in Rome, N.Y., visibility was 10 miles, there was slight rain and winds of about 13 to 14 mph, according to National Weather Service meteorologist Brian Montgomery.
Angel Flight Northeast said since it was founded in 1996 the group has set up free air transportation and medical care for more than 65,000 children and adults on about 60,000 flights covering a total of more than 12 million miles.