BIDDEFORD – The wreckage of a light plane that crashed on a rugged mountainside in western Maine, killing all four people aboard, will remain at Biddeford Municipal Airport during the investigation into the cause of the tragedy.

After being lifted off Barker Mountain by helicopter, the remains of the Cessna 172 were hauled by truck Sunday evening to a hangar where they will remain secured during the investigation by the National Transportation Safety Board.

Killed in the Thursday afternoon crash were the pilot, William Charles Weir, 24, of Auburn, and three Lewiston High School students enrolled in an Air Force Junior ROTC program: Nicholas Babcock, 17; Shannon Fortier, 15; and Teisha Loesberg, 16.

After spending two days examining the wreckage and arranging for its removal to Biddeford, NTSB investigator Todd Gunther returned to Washington, D.C., to continue his work.

Gunther will be contacting potential witnesses and looking at weather conditions, aircraft maintenance records and the pilot’s training and experience, said Paul Schlamm, a spokesman for the agency. “There’ll be further work to be done,” he said.

Within a week, the NTSB will post on its Web site a brief factual statement about the crash, Schlamm said. “Then, some months down the road there will be a more detailed factual report. And after that, will come a final report with a determination or cause,” he said.

Such investigations generally take between six months and a year, Schlamm said, and in most cases the cause of the crash is determined.”

As families made funeral arrangements for the four victims, about 75 students and parents walked Sunday to the high school and met at the flagpole. Each participant carried a candle in what Principal Gus Leblanc characterized as “a public expression of their sympathy and their solidarity.”