Hess stock (NYSE:HES) started the post-holiday week on a sour note as the company’s stock was plummeting following a protest in Venezuela regarding one of its latest projects.

The energy company fell the most it had in nearly three years, eliminating $1.5 billion in the company’s market valuation due to a Venezuelan protest that put a stop to one of its most exciting international investments. This intervention was designed to derail the development of a 5 billion-barrel discovery located off the coastline of Guyana.

The project is very important for Hess’s future growth ambitions and it is the most important item on its investor presentations at the moment. The goal with the Guyana project is to help increase its production growth and cash flow as it heads into the next decade.

Citizens of Venezuela have been pushing back against Guyana’s offshore claims for a long time and protestors took an aggressive approach in interrupting the company’s effort to map the sea floor on Dec. 22, according to a statement from U.S. State Department Deputy Spokesman Robert Palladino on Sunday. The project is being led by Exxon.

Venezuelan vessels had already withdrawn by early Monday following the protests.

HESS stock managed to recover later in the day, eventually rising back up by 9.3% on Wednesday. The company’s stock had been falling by about 12% earlier in the day.