Mexican drivers are waiting in line for hours to cross California’s southern border so they can fill up on U.S. gasoline, because Mexican protesters have blocked fuel distribution centers near Mexicali.

“Right now, it’s crazy,” Rodrigo Marquez, 30, an employee of Antunez’s Shell gas station in Calexico, California, said. “We are having a lot, lot of [Mexican] people, everybody is fueling up their tanks.”

Mexicali drivers wait about four to five hours to cross into the United States to fill up on gas and then wait another two hours to cross back into Mexico again, Bloomberg Markets reported.

The protests curtailing fuel distribution are the result of Mexico’s 20 percent hike in fuel prices. The hike is intended to attract fuel imports and promote competition. Petroleos Mexicanos, also known as Pemex, is struggling to keep its stations supplied with enough gasoline.

Prices have gone up in Mexicali to $2.815 a gallon in January. Over in El Centro, California, prices rose to an average of $2.736 a gallon as of Wednesday.

The demand from Mexico may continue to push up prices in southern California, where prices rose about 11.8 cents in towns by the U.S.-Mexico border.

Mexico’s fuel crisis has also caused protesters in other parts of the country such as Monterrey to turn to rioting, looting and vandalism.

The protesters are calling for Mexican President Enrique Peña Nieto to resign as a result of the skyrocketing prices of gasoline in the country.