LINCOLN — The man who crashed his car into Lincoln High School on Oct. 3 committed suicide moments later by dousing himself with a flammable liquid and setting himself ablaze with a butane lighter, according to a report released yesterday by the state fire marshal’s office.

The report by fire marshal’s investigator David W. Scott said Jay D. Paul, 34, of Cumberland, a teacher’s assistant at the school, had to be identified through dental records. Paul, the only one injured in the crash, died of “thermal injuries with smoke inhalation and burns” as a result of the fire. Scott said the state medical examiner’s office ruled the death a suicide.

Police Chief Brian W. Sullivan and Supt. Georgia Fortunato could not be reached for comment.

The fire marshal’s report confined itself to the specifics of how the car hit the school and the damage that the collision and fire caused. It did not offer any significantly new information about the crash, but did provide details and official confirmation of much that had been offered by witnesses that day.

Scott’s report for the fire marshal’s office said Paul drove through the metal doors of a secondary entrance to a hallway that separates two classrooms and the school’s gymnasium in the one-story brick school building. The concrete-and-steel structure of the doorway prevented the car from penetrating too far into the building, Scott said.

The car showed collision damage to the front bumper, hood and fenders, the report said. The passenger area sustained the most damage, the report said.

Scott said Paul was seen pouring a liquid on himself as he sat in the car after the crash and then used a “gas grill-type” butane lighter to set himself on fire.

The fire devoured everything that could burn inside the car, including Paul’s clothes. It spread to the walls, ceiling and floor of the entryway and then scorched the wall and ignited paper and books in the two classrooms. The gym sustained some smoke damage, but the fire did not spread. In the days after the crash, school officials said food for the cafeteria kitchen had to be thrown away because smoke spread to the food storage area.

The school reopened the following Monday, after maintenance workers spent the weekend repairing the damage. The hole in the side of the building was closed by a beige wall with a wooden door. The walls of inner corridor were covered with gray wallboard and dropped ceilings had all been replaced.

The crash occurred on a sunny Friday afternoon, about an hour after classes had ended. Students at the scene that day said they had seen Paul with Principal Kevin McNamara and Assistant Principal Charlotte Tavares at about 2:30 p.m., apparently being reprimanded for something.

The police have said Paul then left, returning shortly before 3 p.m., when he crashed his car into the building.

Sullivan, the police chief, has not commented on the specifics of his department’s investigation, saying he was waiting, among other things, for the fire marshal’s report. He has said Paul did not leave a suicide note.

Paul grew up in the Lime Rock section of Lincoln, where he was an honor roll student throughout his academic career in the town’s schools, winning awards for excellence in social studies, science and French. He won the district’s annual spelling bee while in elementary school and again in junior high school.

As a seventh grader, he had the highest verbal score among junior high students in the state who took the SATs, a 630 (out of 800), according to a Journal story at the time.

Neighbors in Cumberland said Paul was quiet and kept to himself.

jhill@projo.com