Juba - "In September there was no fuel anywhere," Samson Kamuya says.The exhausted 45-year-old hangs his head. He's been waiting four days at a fuel station in South Sudan's capital, Juba, to no avail.Wedged among hundreds of cars, trucks and desperate civilians carrying empty jerry cans, he says the fuel situation is unlike anything he's seen in his eight years as a driver.It is a cruel irony in the world's youngest nation: 98% of South Sudan's economy comes from oil, but the country faces one of its worst fuel crises since civil war began in 2013.South Sudan has Africa's third-largest oil reserves, with 3.5 billion barrels. Based on government figures, current production should bring in hundreds of millions of dollars a year. But without refineries, the country exports crude oil and must import fuel.Some have accused government corruption of worsening the country's overall crisis. South Sudan soon will enter its fifth year of fighting amid starvation, mass displacement and allegations of war crimes."Instead of using oil revenue to provide public services and improve the livelihoods of South Sudan's population, the ruling clique has used these funds to procure weapons, finance a horrific civil war and enrich themselves," says JR Mailey, director of the investigative team at The Sentry, a Washington-based group.Black market"The money's being kept abroad," a member of South Sudan's parliament, who spoke on condition of anonymity for fear of his safety, told The Associated Press. The money the government should be receiving for oil exports is enough to fuel the entire country, the lawmaker says.Civilians feel the brunt of the crisis. Drivers like Kamuya often hire people to sleep in their parked cars at the pumps while they borrow other transport to keep working.Kamuya says he has been forced to buy fuel on the black market for almost 10 times the usual price. In addition, government soldiers have been accused of threatening civilians at fuel stations and cutting in line to stock up on fuel to sell illegally."If someone tells you to move with a gun you can't argue," says Simon Kinuthia, a driver in Juba.The army denies the allegations.