CNN | September 13, 2001

SHANKSVILLE, Pennsylvania (CNN) -- Searchers Thursday found one of the so-called black boxes from United Airlines Flight 93, the hijacked airliner that crashed Tuesday in western Pennsylvania.

The flight data recorder was found in the crater the plane created when it slammed into the ground Tuesday morning, according to FBI spokesman Bill Crowley.

"We are hoping that it will have some information that is pertinent to what occurred in the plane prior to its crashing," Crowley said.

The recorder is being sent to the National Transportation Safety Board in Washington for analysis, Crowley said.

They are still searching for the voice data recorder.

Meanwhile, investigators say they've found debris from the crash at least eight miles away from the crash site.

A second debris field was around Indian Lake about 3 miles from the crash scene. Some debris was in the lake and some was adjacent to the lake.

More debris from the plane was found in New Baltimore, some 8 miles away from the crash.

State police and the FBI initially said they didn't want to speculate whether the debris was from the crash, or if the plane could have broken up in midair.

Investigators later said the debris was all very light material, such as paper and thin nylon the wind would easily blow. The wind was blowing towards Indian Lake and New Baltimore at 9 knots. "According to the NTSB, it is not only possible that the debris is from the crash, it is probable," Crowley said.

The Boeing 757, which was bound for San Francisco from Newark, was among four planes hijacked Tuesday in the worst terror attack in U.S. history. It crashed in Shanksville in Somerset County, 80 miles southeast of Pittsburgh.

Officials said an engine part has been recovered. Much of the debris is tiny.

Also Thursday, the National Transportation Safety Board confirmed that the flight had been headed east. The plane, which took off from Newark bound for San Francisco, was diverted somewhere around Cleveland.

Information from a telephone call made by a passenger indicated that passengers on Flight 93 tried to wrest control from the hijackers, which may have caused the plane to crash before it reached whatever target the hijackers were aiming for. All 45 people aboard were killed.

Officials have speculated the hijackers may have been planning to ram the plane into the Capitol, the White House or Camp David. The other planes crashed into the World Trade Center and the Pentagon.

As the recovery process at the crash scene in western Pennsylvania continues, emergency workers are painstakingly looking for human remains, airplane parts and personal effects.

FBI officials leading the investigation say it could take weeks to recover everything from the site. Forensic anthropologists and hazardous material inspectors are among those at the scene.

Families of the victims are expected to arrive in the area Thursday. United Airlines is hosting them at a nearby resort.

-Correspondent Brian Cabell contributed to this report