The National Highway Traffic Safety Administration is demanding that ARC Automotive Inc. of Knoxville recall 67 million inflators in the U.S. because they could explode and hurl shrapnel.

The warning covers vehicles from the 2000 through 2006 model years that previously had been recalled to replace the faulty and dangerous air bag inflators.

The warning came after air bags apparently exploded in three more cars, killing the drivers. Affected models include Chargers and Chrysler 300 sedans from the 2005 through 2010 model years.