Fuel deliveries from Niger’s only oil refinery were disrupted by the start of a three-day strike over working conditions and pay, a local union official said, Reuters informed.

The Soraz refinery, a joint venture between China National Petroleum Corp (CNPC) and the Nigerian government, processes about 12,000-16,000b/d, offering Niger’s only large-scale means of transforming crude oil into petroleum products such as gasoline.

“The strike is well observed,” the oil workers union’s spokesman, Cisse Amadou, said. “The loading of the tankers is almost paralyzed. Usually we load around one hundred fuel trucks per day, at this moment only a dozen have been loaded,” Fin24 wrote.

It is not the first time that this kind of problems are reported, last year, the workers at the plant, which employs over 400 Nigerians, launched a series of protests because of discrepancies in pay between local and Chinese employees.

The refinery is located 800 km east of the capital, Niamey, and processes crude from CNPC’s fields in the Agadem zone in the east for supply to the domestic market and to importers in Mali and Burkina Faso.