FBI finished with Pennsylvania crash site probe

SHANKSVILLE, Pennsylvania (CNN) -- The FBI announced Monday that its investigation of the site where a hijacked jet slammed into a field here is complete and that 95 percent of the plane was recovered.

The federal investigation into the September 11 terrorist attacks continues.

Evidence-gathering was halted Saturday afternoon and the pieces of United Airlines Flight 93 that had been recovered were turned over Sunday to the airline, with the exception of the flight data recorder and the voice recorder, which are being held and analyzed by the FBI, according to FBI agent Bill Crowley.

Crowley said the biggest piece of the plane that was recovered was a 6-by-7-foot piece of the fuselage skin, including about four windows. The heaviest piece, Crowley said, was part of an engine fan, weighing about 1,000 pounds.

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Flight 93 was one of four jets hijacked Sept. 11. Authorities believe the flight, which originated in Newark, New Jersey, and had been destined for San Francisco, was headed for the nation's capital, where the hijackers may have intended to slam it into the White House or the Capitol.

Attorney General John Ashcroft and FBI Director Robert Mueller have praised the passengers of that flight, saying it appears their actions in trying to regain control of the aircraft averted a greater tragedy.

People who spoke by phone with passengers after the plane was hijacked say that after the passengers found out about the earlier World Trade Center attack, they decided to try to overpower the hijackers.

And officials familiar with the flight's cockpit voice recorder say it shows there was a "definite struggle," which they described as desperate and wild, between hijackers and some of the passengers.

All 44 people on board the flight were killed when it slammed into the ground.