Replacement airbag inflators in used cars in the U.S. have killed three people and caused life-altering, disfiguring injuries in two others in the last nine months alone, federal officials warned on Wednesday.

The deaths and injuries stem from vehicles previously involved in crashes in which the original airbags were replaced with defective inflators, most of which were manufactured overseas, the National Highway Traffic Safety Administration said in a consumer alert.

“These dangerous aftermarket parts malfunctioned in subsequent crashes, sending large metal fragments into drivers’ chests, necks, eyes and faces, killing or severely injuring drivers in otherwise survivable crashes,” NHTSA said.

Such replacement parts are often made by foreign companies with little reputation for quality, and are typically sold at prices far below the cost of genuine equipment, the agency said, referring to the components that the led to the three deaths and other injuries as “faulty, cheap, imported aftermarket air bag inflators.” 

The parts are often ordered online, shipped to the U.S. and installed at less reputable repair shops, according to regulators. NHTSA urged people who own or are buying a used vehicle to learn about its history to ensure it has genuine airbag inflators, as an inadequate replacement part could kill or critically injure them in a crash. 

“Additionally, these inflators may deploy partially or too slowly, failing to protect an occupant’s head from striking the steering wheel or dashboard,” the agency said.

More specifically, NHTSA is advising people to: 

• Obtain a vehicle history report. If the vehicle has been reported in a crash where the airbag deployed, motorists should visit a reputable independent mechanic or dealership for an airbag inspection to ensure the parts are genuine.
• Do business with reputable independent mechanics and manufacturer dealerships. When considering a purchase from a private seller, obtain a vehicle history report and have the vehicle inspected by a trusted mechanic.
• Ask about the replacement parts when having a vehicle serviced, including the brand and origin of the parts.
• Buy with caution when looking at automotive parts online from overseas retailers or sold at prices well below competitors. 

If used vehicle owners are concerned they might be driving a car with a faulty replacement inflator, the government advises contacting their brand’s dealership or a reputable mechanic to determine if the parts need to be replaced. 

Owners whose vehicle has one of the suspect inflators should contact their local Homeland Security Investigations office or FBI field office to report it. Complaints may also be submitted online. Consumers can also contact NHTSA online or by calling the agency’s hotline at (888) 327-4236 Monday through Friday, 8 a.m. to 8 p.m. Eastern time.