A Comair flight carrying 50 people crashed shortly after take-off from Blue Grass airport in Lexington, Kentucky, on Sunday morning, killing 49 onboard, the Federal Aviation Administration (FAA) said.
Comair President Don Bornhorst told a press conference that only one person survived the crash. Comair Flight 5191, a CRJ-100 regional jet, crashed shortly after taking off.
He would not confirm news reports that the survivor was the pilot of the plane.
Bornhorst added that the plane was subject to routine maintenance program, the last round being the Monday before the crash.
CNN earlier reported that at least one survivor was being treated in the University of Kentucky Hospital, and is in critical condition.
A temporary morgue has been set up at the crash site and bodies will be brought to the Kentucky state medical examiner's office.
Local coroners said the deaths were caused either by the impact or the resulting fire onboard.
The plane was leaving Blue Grass Airport in Lexington and was headed for Atlanta when it went down in woods about 1.6 kilometers from the airport at about 6:07 AM local time (10:07 GMT). It was raining lightly at the time.
Bornhorst said the airline is patching up all the information about the crash but it needs time to get the complete picture.
He said Delta, the parent company of Comair, has set up an information phone line for relatives of those aboard the crashed plane.
Comair, a regional carrier based in Cincinnati, is a unit of Delta Air Lines Inc.
The airport closed for three hours after the crash, but was reopened by 9 AM (13:00 GMT).
There was no immediate word on what caused the crash. The plane was largely intact afterward, although there was a fire following the impact.
Some experts said the crash could have been engine-related.
According to the latest news reports, flight recorders have been found.
The Bombardier Canadair CRJ-100 is a twin-engine aircraft that can carry up to 50 passengers.
The crash spells the end of what has been called the "safest period in aviation history" in the US. Before this, there hadn't been a major crash since November 12, 2001, when American Airlines Flight 587 plunged into a residential neighborhood in Queens, NY, and killed 265 people.
(Xinhua News Agency August 28, 2006)