WASHINGTON – A minor who was driving a car that crashed near Pittsburgh has been tentatively identified by the government as the eighth death in the U.S. due to an explosive air bag inflator made by auto parts maker Takata, federal transportation officials said Wednesday.

The National Highway Traffic Safety Administration officials also announced an expansion in the recall of vehicles with Takata airbags, already the largest and most complex recall in the agency’s history. The latest findings could result in the recall of several hundred thousand additional vehicles, officials said.

The appointment of an independent monitor to oversee the company’s compliance with a government consent order on the recalls was also announced.

NHTSA learned of the latest death last week after a lawyer for the minor’s family contacted the agency, NHTSA spokesman Gordon Trowbridge told reporters in a conference call. The car involved was a used 2001 Honda Accord under recall that was owned by a relative of the minor, he said. But a government official told The Associated Press that a boy was driving the car when it left the road and struck a tree. The official provided the information on condition of anonymity because he wasn’t authorized to speak publicly.

“The agency has now tentatively concluded that this was likely a rupture-related fatality,” Trowbridge said. The agency is now working the family, Takata and Honda to examine the vehicle in order to confirm that conclusion, he said.