Detecting lies for a living can be difficult, tedious work.

To do it well requires an analytical mind, an attention to detail and a tenacious desire for the truth, said Bryan D. Horaist, a polygrapher with the Air Force. And he said of all the people he's worked with, Rick A. Ulbright of Waldorf was one of the best.

"Probably more than anyone I've ever known, [Ulbright] really was a dedicated and professional special agent," said Horaist. "He had a character well suited to this work. He was very methodical and very thorough. He was in it until the end. He wasn't going to give up."

Last Sunday, after completing a polygraph examination at Kirkuk Air Base in Iraq, Ulbright, 49, was killed by a rocket attack while walking outside, Horaist said. He was the first member of the Air Force Office of Special Investigations to be killed in Iraq and the fourth combat death in the history of the office, said Capt. Regen Wilson, a spokesman for the investigative unit.

"It's caught us all off-guard," he said.

Ulbright had retired from active duty with the Air Force in 1998 after 21 years of service and had been working since then as a civilian with the 33rd Field Investigative Squadron based at Andrews Air Force Base, military officials said. He had been on a temporary assignment in Iraq and was expected to return to his home in the Huntington neighborhood of Waldorf early next month, authorities and neighbors said.

Members of Ulbright's family have declined to speak about him. They held a service Friday in a chapel at Andrews Air Force Base.

A news release from the Air Force provides some detail about his life: He was born in Washington state and graduated from high school and attended college in Boise, Idaho. He began his military career as a helicopter maintenance technician in 1978.

After several years as an aircraft crew chief and supervisor, he completed a degree in criminal justice and joined the Office of Special Investigations as a criminal investigator and later became a polygraph examiner. In Iraq, his work was for polygraph support "geared toward counterterrorism and counterintelligence efforts of all the service branches," Horaist said.

Ulbright had two grown daughters and one granddaughter; he lived with his wife, Karen, in Waldorf. On first impression, Ulbright could act reserved, Horaist said, but after warming up he was "a prankster and a very happy person."

His neighbors described him as quiet but unfailingly friendly. Tim Burkhart, 39, who lives next door, said he often saw Ulbright mowing the lawn or lounging by his backyard swimming pool. They never spoke for long, but the exchanges were always pleasant.

"Rick was a very nice guy; that's why it's such a shock," Burkhart said. "He was an outstanding person."