Federal investigators

National Transportation Safety Board spokesman Eric Weiss said the black boxes from British Airways Flight 2276 have arrived in Washington, D.C., and an NTSB team in Las Vegas could provide preliminary findings as early as Thursday.

The London-bound plane was accelerating down the runway Tuesday when its left engine burst into flames. The takeoff was aborted, the plane's slides were deployed, and the 170 passengers and crew escaped the Boeing 777 without serious injury.

The Bureau of Alcohol, Tobacco, Firearms and Explosives and the Anne Arundel County Fire Department released a report Wednesday that says there were numerous hazards identified at the mansion. It says the primary hazard was that while the castle-like mansion was residential, it was built like a commercial building.

Investigators concluded the blaze was accidental. The report says other potential causes were identified and analyzed, but all were eventually discarded.