A person briefed on the matter says the Justice Department is investigating whether General Motors broke any laws with its slow response to a deadly problem with ignition switches on certain small cars.
The probe is being handled by the U.S. Attorney's Office in New York, said the person, who asked not to be identified because the investigation is not public.
A Justice Department spokesman did not immediately return calls. GM would not comment.
GM already is facing investigations by Senate and House committees and the National Highway Traffic Safety Administration.
Last month GM announced the recall of 1.6 million older compact cars worldwide to replace ignition switches that can shut off the motor unexpectedly. GM says the problem is linked to 13 deaths.