MARACAIBO/PUNTO FIJO (Reuters) - Soldiers oversaw rationing of gasoline at service stations in several parts of Venezuela on Sunday as worsening fuel shortages forced angry drivers to wait for hours to fill their tanks, prompting protests in some areas.

FILE PHOTO: A man walks past fuel containers while vehicle queue to refuel with gasoline in Puerto Cabello, Venezuela May 17, 2019. REUTERS/Manaure Quintero/File Photo

Venezuela, whose economy is reeling from a five-year recession amid a prolonged political crisis, saw long lines of vehicles appear at services stations in several regions this week after a shutdown at the OPEC nation’s second-largest refinery.

Shortages have been exacerbated by tough U.S. sanctions on Venezuelan state oil firm Petroleos de Venezuela SA (PDVSA) in January, which have slashed crude oil exports and imports of refined fuels.

Washington recognized opposition head Juan Guaido as Venezuela’s rightful leader after he invoked the constitution in January to declare an interim presidency, saying President Nicolas Maduro rigged last year’s election.

Maduro calls Guaido a U.S. puppet and says Washington wants to control Venezuela’s oil reserves, the largest in the world. Dozens of people have been killed in political protests this year.

In the western city of San Cristóbal, close to the Colombian border, National Guard soldiers in anti-riot gear limited gasoline sales to 40 liters (10.6 gallons) per vehicle, witnesses said - roughly equivalent to a full tank on a compact vehicle.

Angry residents blocked streets with metal barriers, rubbish and branches in some parts of the city. At some gasoline stations, people said they had been waiting days for fuel.

“How can a country function like this?” asked Antonio Tamariz, 58, who said he had waited for days for fuel to drive his truck back to his farm. “No one has explained why there are so many lines for gasoline. I think the government is losing control of this.”

Venezuela’s Information Ministry - which handles media enquiries for the government - did not respond to requests for comment.

Oil Minister Manuel Quevedo said on Sunday his country’s oil industry was under siege from the U.S. government, causing supply problems.

In the southeastern industrial hub of Puerto Ordaz and the northwestern city of Punto Fijo, close to Venezuela’s largest refining complex, soldiers were ordered to deliver 40 and 30 liters respectively, according to a dozen witnesses.

In the western oil hub of Maracaibo, where power cuts and fuel shortages have been severe in recent months, National Guard soldiers allowed drivers only 20 liters (5.3 gallons) of fuel, witnesses said.

“They have taken control of the pumps,” said Rocio Huerta, a manager of a service station in Maracaibo. “Every five hours there are inspections by the Military Intelligence Division to measure how much gasoline is left.”

Victor Chourio, a 58-year-old taxi driver, said he had arrived at the gasoline station early on Saturday and waited for 12 hours without getting fuel.

“At two o’clock in the afternoon a soldier guard said only 20 liters per vehicle ... but at seven o’clock the gasoline ran out,” Chourio told Reuters.

Venezuela’s 310,000 bpd Cardon oil refinery - which had been operating well below capacity - halted operations on Wednesday because of damage at some of its units, two workers at the PDVSA-operated complex said. That left only two refineries in operation in Venezuela.

Internal PDVSA documents and Refinitiv Eikon data indicate that Venezuela had not imported a gasoline cargo since March 31.

The fuel shortages come on top of rolling powercuts in many parts of Venezuela as the government attempts to rotate electricity supplies to avoid a repeat of March’s week-long national blackout.

In Caracas, home to roughly a fifth of Venezuela’s more than 30 million people, there were few signs of widespread gasoline shortages as Maduro has prioritized services to the capital.

PDVSA said in a statement on Sunday that it had sufficient fuel inventories to provide reliable gasoline supplies. It denounced rumors “seeking to destabilize normal fuel distribution and drive panic buying”, without mentioning the long lines at services stations and rationing of fuel in some areas.

PDVSA did not respond to a request for more information.

In some cities, security forces set up special gasoline pumps to deliver fuel for ambulances, medical personnel and official vehicles, a measure that aroused criticism among people who remained waiting in lines often stretching for several kilometers.

Some drivers complained that fuel rationing meant they would again be forced to wait for hours within just a few days.

“This is not enough at all, between going to work and taking my children to school. It will run out in two days,” said Eduardo Pereira, a 47-year-old teacher in Puerto Ordaz, who was only allowed to buy 40 liters of fuel.