Updated

Another Tesla Model S electric car has caught fire, this time after hitting road debris outside of Smyrna, Tennessee.

The blaze on Wednesday afternoon engulfed the front of the car. A spokeswoman for the Tennessee Highway Patrol says the Model S was headed east on Interstate 24 when it ran over a tow hitch. The hitch hit the undercarriage of the car, causing an electrical fire.

It's the third fire in a Model S in the past five weeks and similar to one in early October just outside of Seattle. In that fire, a driver hit road debris that pierced a shield and the battery pack, causing a fire. The other blaze happened in Mexico after the driver ran over a roundabout and crashed into a concrete wall and a tree at a high speed.

The Model S, which starts at $70,000, can go up to 265 miles on a single charge.

In the Tennessee case, the driver was able to pull onto an emergency lane. No one was hurt.

Tesla says the fire was not spontaneous. Spokeswoman Liz Jarvis Shean says Tesla has sent a team to Tennessee to investigate the fire. She says the company has been in contact with the driver, who believes the car saved his life.

The fire burned the front of the car, according to pictures posted on the Jalopnik.com and Valuewalk.com websites.

Shares of the carmaker, based in Palo Alto, Calif., fell 7 percent Thursday morning to $140.63.

The high-flying stock had risen in value by more than 400 percent earlier in the year, but fell this week after some analysts found its third-quarter earnings disappointing. Concerns about a battery shortage, as well as the costs Tesla will incur as it builds more cars, spooked some investors.