Shares for Tesla are down 6.5 percent from yesterday, after a video of a burning Model S went viral on YouTube, racking up almost half a million views in two days.

As the driver told it to troopers, he was going south on Route 167 in Washington Tuesday morning when he hit some metal debris in the road. He exited the highway, and the vehicle became disabled. Shortly after, it caught fire.

Here's what that looked like:

The official crash report is not yet in, but Tesla was quick to defend itself. In a statement Wednesday, the automaker said the fire was caused by "substantial damage sustained during the collision," and "was contained to the front of the vehicle thanks to the design and construction of the vehicle and battery pack. All indications are that the fire never entered the interior cabin of the car."

Still, it could be something of a reality check for the automaker, which has spent the last few months warming in the glow of Wall Street's favor. Since the beginning of the year, the company has reached profitability, while the demand for the $70,000 Model S has risen, sending the stock price up more than 400 percent.

The good vibes got stronger when the Model S tied for the highest auto ratings ever from Consumer Reports magazine this spring, and when the Model S earned top crash-test scores from the National Highway Traffic and Safety Administration in the summer.

However, skeptics have warned that the share price is getting out of hand. Analysts estimate growth at 18.7 percent — meaning it would take five years for the company to grow into its current valuation. Even founder Elon Musk has hinted that the price is too high, saying in a CNBC interview in August that "the market is being very generous," and adding, "Our stock price is obviously too high based on historical financials or even current financials."

The market's quick reaction to the fire seems to prove Musk right. An inflated stock price can fall fast on a hint of bad press. We still don't know what caused the fire, but some have pointed out that lithium ion batteries — similar to the kind in the Model S — have been proven dangerous in other vehicles. Here's TIME:

Two years ago, battery fires broke out in three Chevrolet Volt plug-in hybrid cars after crash-testing, but NHTSA investigators determined that the Volt was no more risky than vehicles with conventional gasoline engines.

Officials from General Motors Co. and the government believe the fires were caused by coolant leaking from damaged plastic casing around the batteries after side-impact test crashes. At the time, they said there were no real-world fires in any Volts.

Still, the fires tarnished the Volt’s reputation and cut into sales. Recently, though, sales of the car have recovered. Sales are up about 3 percent this year, with GM selling about 17,000 through September. [TIME]

In addition, Ben Kallo, an analyst at Robert W. Baird & Co., downgraded the stock to neutral from outperform after the fire, further freaking out investors. Bloomberg says:

The electric-car maker is increasing output of its Model S sedan and plans to introduce a Model X sport-utility vehicle and "any hiccups in execution present stock-price risk in the near to intermediate term," Kallo wrote in a report. [Bloomberg]

It may well be that fire was not Tesla's fault. And the automaker is correct that it would have been worse were it not for the car's ultra-safe design. But the sharp reaction on Wall Street shows how unstable a hot stock can be.