LAGOS, Nigeria — Young men became entangled in a swirl of flying fists. Gas station workers swatted away boys hoping to fill their plastic cans. A mother with a sleeping baby in her minivan was chased off, rightly accused of jumping the line. A driver eager to get ahead crashed into several cars, the sound of crunching metal barely registering amid the noise.

Nigerians were getting used to days like this.

But then came the ultimate insult to everyone waiting at the Oando mega gas station: A bus marked Ministry of Justice rolled up to a pump, leapfrogging no fewer than 99 vehicles. “Service With Integrity” was painted on its door. A gas station supervisor who calls herself Madame No Nonsense stepped aside to let it fuel up before anyone else. The crowd howled at the injustice.

Plummeting oil prices have set off an economic unraveling in Nigeria, one of the world’s top oil producers, and the collective anger of a fed-up nation was pouring out.

“Starvation in the land of plenty,” said Tony Usidamen, a public relations consultant waiting for fuel.