As a state police fire marshal and criminal investigator, Trooper John F. Marshall has seen his share of gruesome crime scenes.

So, when many members of his troop in Uniontown were sent to neighboring Somerset County to help secure and investigate the Sept. 11 crash of hijacked United Airlines Flight 93, the Greenville native didn't consider the assignment anything out of the ordinary.

Marshall, who has served in Uniontown since joining the state police in 1990, and other members of his troop had been sent to Beaver County when a USAir jet crashed a few years ago.

"It was just what the Pennsylvania State Police do every day," Marshall said of the Flight 93 response. "This is what the people of Pennsylvania count on."

But when his mind wasn't so focused on his job, Marshall acknowledged that the Flight 93 crash was different.

"It took a personal toll on everybody," said the 1978 Greenville High grad. "We're the Pennsylvania State Police, but this was an attack on America."

The Uniontown troop is one of the largest in the state, and 52 members were initially assigned to the crash site.

The troop's primary responsibility was security. One set of troopers manned an exterior perimeter. while another group worked closer to the crash site in case anyone got past. No one did.

"We had everything blocked up here pretty good," said the son of Cyril and Maryann Marshall of Hempfield Township.

For the first two or three days, Marshall walked the surrounding countryside looking for airplane parts.

"I found a lot of parts," said Marshall, who was awarded a 2000 Law Enforcement Agency Directors award for identifying a man nearly four years after he was found murdered.

"The biggest part I found was one of the plane's engines. It was about 600 yards from the crash site itself. I think they took it out with a winch on a bulldozer."

Marshall, who served four years in the Air Force, said he found many parts that he couldn't specifically identify.

Whenever he found a suspected part, he would notify the FBI or United employees.

Marshall, who lives in Uniontown with his wife, Kim, and 13-year-old stepson Brent, spent about eight days at the site, and his troop has resumed its normal duties in its home county of Fayette.

Even though the investigation involved many agencies and was watched closely by a national audience, it was quickly set up and organized.

"The incident command center, from the minute we got there, it ran so smooth," he said. "That's what we train for."

Marshall's children, Ashley, 16, John Jr., 13 and Luke, 9, live in Greenville.