The FBI laboratory in D.C. received boxes of evidence from local police. Among the items were segments of a chair, rubble from the walls, and portions of apartment rugs.
After three weeks of examining the evidence, the FBI gave some explanations, although they didn’t provide answers.
The Bureau found no trace of accelerants or combustible liquids such as gasoline and alcohol; the fire would have consumed them if they existed in the scene.
All fuses were found intact, ruling out the possibility of electric malfunction. They ruled out some cases yet offered no conclusive answer.