What happened 

Shares of Nikola (NKLA 2.27%) fell sharply on Thursday after Hindenburg Research published a scathing report on the electric truck maker. As of 11:15 a.m. EDT, Nikola stock was down 10%. 

So what

Hindenburg Research -- a noted short-seller -- accused Nikola of being "an intricate fraud built on dozens of lies" in its report published today.

"We have gathered extensive evidence -- including recorded phone calls, text messages, private emails, and behind-the-scenes photographs -- detailing dozens of false statements by Nikola Founder Trevor Milton," Hindenburg wrote. "We have never seen this level of deception at a public company, especially of this size."

A downwardly sloping stock chart.

Nikola stock plummeted on Thursday following a report by short-seller Hindenburg Research. Image source: Getty Images.

The report goes on to claim that Nikola has repeatedly hyped its battery and fuel cell technology beyond its true capabilities and overstated its progress toward the development of its electric truck.

Hindenburg also argues that Nikola's recent $2 billion deal with auto giant General Motors (GM -6.42%), which will supply the batteries and fuel cells for its electric tractor-trailer trucks, provides more evidence that Nikola inflated its own technological capabilities.

Now what

Nikola founder and executive chairman Trevor Milton responded to Hindenburg's report on Twitter, saying "This is all you got?" He also promised to respond to Hindenburg's "lies" in more detail later in the day.

Nikola's shareholders are no doubt eagerly awaiting Milton's rebuttal, which could help the stock rebound, depending on what he has to say.