For most of this year, Tesla Motors has looked like the next Google or Apple.

Its stock soared about 470% as Wall Street analysts characterized the business as a small but revolutionary automaker that acted like a tech company — disrupting the status quo with its sporty, high-end electric cars.

It turns out there are some potholes in Tesla's path.

The automaker confirmed Thursday that a fire burned up one of its $70,000-plus Model S hatchbacks. It was the third such incident in five weeks and triggered calls for a federal safety investigation.

Meanwhile, car shopping website and auto reviewer Edmunds.com said its has encountered mechanical problems in its Tesla that have forced the replacement of numerous parts, including the entire drivetrain.

A battery supply bottleneck, heavy research and development spending and declining sales of lucrative environmental credits also have created head winds for the Palo Alto automaker. Several Wall Street analysts have cut their price targets for the company, and Efriam Levy of Standard & Poor's has recommended selling the stock.

"Tesla still has to follow the laws of physics, just like any other car company," said Thilo Koslowski, an analyst at Gartner Inc.

Tesla Motors Inc.'s shares soared from $33.87 on Dec. 31 to its all-time high of $193.37 on Sept. 30. The growth was powered by brisk Model S sales, a glowing review from Consumer Reports, top results in federal crash tests and more than $100 million in sales of regulatory environmental credits to other automakers.

But since then — mostly this week — Tesla stock has plunged 28%, including 7.5% Thursday, to $139.77.

"People realized that the stock was probably at a higher price than it should have been," Koslowski said. "This is a correction."

The latest fire was after a crash Wednesday near Smyrna, Tenn. That followed fires in two other Model S hatchbacks, the first in Seattle and the second in Mexico. Both cars were in crashes, and the fires injured no one.

Normally, car fires don't influence investors. There are about 150,000 annually, according to the National Fire Protection Assn. However, safety officials have been tracking fires in electric cars, as well as airplanes, computers and other equipment, out of concern that lithium-ion battery systems might be prone to fires.

But three fires associated with crashes of new cars — as opposed to battered, older gasoline vehicles produced under less-stringent safety standards — are a matter of concern, said Clarence Ditlow, executive director for the Center for Auto Safety.

"There is no question that the National Highway Traffic Safety Administration should start looking at this," Ditlow said.

Koslowski said people shouldn't be alarmed by the fires but said they do raise questions that Tesla and regulators should answer.

"How many Teslas were in an accident and didn't catch fire?" he asked. "We need to know how frequently the battery ignites following an accident."

NHTSA reviewed the Tesla fire in Seattle and concluded it was caused by the accident rather than a vehicle defect.

Tesla said it contacted the driver of the car in Tennessee and noted he "believes the car saved his life. Our team is on its way to Tennessee to learn more about what happened in the accident."

Separate from questions of safety, these repeated incidents are taking a toll on Tesla, said Karl Brauer, an analyst at car information company Kelley Blue Book.

"For a company with a stock price based as much or more on image than financials, those recurring headlines are highly damaging," he said.