FORT DRUM, N.Y. -- A Black Hawk helicopter carrying 13 people crashed Tuesday in a heavily wooded area of this sprawling Army post, military officials said. Two people survived, but authorities did not disclose the fate of the other 11 aboard.

"I would like to extend my condolences to the families of our fallen comrades and I want to assure you that we will fully investigate this terrible accident and do everything in our power to take care of all the families involved in this tragedy," said Maj. Gen. Franklin Hagenbeck, commander of the 10th Mountain Division.

Military officials refused to take questions at a news briefing.

The helicopter, a widely used transport aircraft, crashed just north of Wheeler-Sack Airfield, Lt. Col. Bryan Hilferty said. He said there was no indication of problems beforehand.

"The first call I got was that it was missing. It just disappeared," Hilferty said. He said he believed the aircraft was on a training mission with at least one other helicopter, perhaps two.

Maj. Daniel Bohr at Fort Drum said the aircraft last made radio contact shortly before 2 p.m. Rescue crew located the crash site at about 3:30 p.m.

Greg Burnelle, a Jefferson County emergency management official, said the helicopter crashed between the tiny towns of Antwerp and Philadelphia in upstate New York. Burnelle said there were "critical injured people."

Hilferty said at least one soldier was spotted walking away from the wreckage. Two soldiers were being taken to Samaritan Hospital and a third was en route to the hospital, spokeswoman Krista Kittle said.

Fort Drum, situated along the eastern shore of Lake Ontario about 70 miles northeast of Syracuse, is home to the 10th Mountain Division and has been a major staging area for reserve units taking part in the build-up toward war with Iraq. Nearly 1,000 division soldiers and reservists have left from Fort Drum in recent weeks.

Black Hawk UH-60 helicopters are widely used transport aircraft. They are equipped with advanced avionics and electronics, such as the global positioning systems.

The training mission had no connection with ongoing war exercises at the base, Hilferty said.