BMW is warning the owners of about 90,000 older vehicles in the U.S. not to drive them due to an increasing threat that the air bags might explode in a crash.

The warning covers vehicles from the 2000 through 2006 that previously had been recalled to replace faulty and dangerous air bag inflators made by Takata. The company used ammonium nitrate to inflate the air bags in a crash. But the chemical can deteriorate over time when exposed to heat and can blow apart a metal canister, hurling shrapnel that can injure or kill drivers and passengers.

Models involved in the recall include the 2000 through 2006 3 Series, the 2000 through 2003 5 Series and the 2000 through 2004 X5. All have driver's front air bag inflators made by Takata.

The National Highway Traffic Safety Administration (NHTSA) said drivers should park their vehicles and contact BMW for more information. Repairs are available at no cost to owners, as well as mobile repair and free towing.... Read More: CBS News