The FBI and Justice Department are now pursuing a criminal investigation against General Motors, focusing on what the largest U.S. automaker told regulators and when -- and what, if anything, it omitted regarding its recent ignition switch recall, ABC News has learned.
Neither GM nor the U.S. attorney has officially confirmed the probe.
In February, GM announced a recall of all 1.6 million cars from model years 2003-07.
According to depositions, however, GM engineers knew there was a problem with the ignition 10 years ago.
The potentially fatal flaw in certain older GM cars has been linked to at least 12 deaths and 31 crashes.
Walter Luba, 61, of Mount Morris, Ill., said he was driving a 2006 Chevy Cobalt in February when out of nowhere, the power shut down and his steering wheel locked. His car smashed into a snowbank and rolled over.
"It was horrifying," Luba said.
Mary Barra, two months into her job as GM's new CEO, said she was conducting an internal review and demanding an "unvarnished" picture of GM's handling of the ignition problem.
"This is a corporate-wide culture problem, and I do think that Mary Barra wants to make up for the mistakes of the past but she's got a lot to make up for," said Joan Claybrook, former head of the National Highway Traffic Safety Administration.
ABC News' Rebecca Jarvis and Diane Mendez contributed to this story.