A bus crash on I-95 in Virginia in May left four people dead.
Federal investigators with the National Transportation Safety Board are launching a probe of the crash in Caroline County, just north of Richmond. They deploy to the scenes of major accidents for buses, trains, airplanes and boats.
NTSB member Earl Weener says, in this case, his team will look at the bus company's maintenance records and driver logs and will evaluate the way these types of buses are regulated.
"What we want to understand is, are there things that can be done to the bus, to its operation, to the operation of the carriers themselves that will prevent these accidents in the future," he says.
Weener says the NTSB investigators will be on the scene for the next seven to 10 days, but the board may not issue a final report for a year or more.
In the meantime, the U.S. Department of Transportation has shut down Sky Express Incorporated, the bus company involved in the crash. The driver is facing reckless driving charges.