A Senior Oil Workers’ Union official said that all oil companies operating in Nigeria should evacuate their staff from the southern Niger Delta following several attacks on oil facilities, Reuters reported.

The recent attacks have pushed Nigeria’s crude output near to a 22-year low, sparking worries that militants might resume a full-scale insurgency in the Delta, a region where many complain of poverty despite sitting on much of the country’s energy wealth.

At the beginning of May, a new militant group known as Niger Delta Avengers attacked a Chevron facility in the Delta after claiming a strike in February against a Shell pipeline, which shut down the 250,000bp/d Forcados export terminal. In addition, it was also reported by Reuters that gunmen killed two policemen in the same region while they were sleeping in a security post, and three soldiers were killed in a second attack, police and the army said.

For his side, Chika Onuegbu, Chairman of the Trade Union in Rivers state, said Chevron had evacuated some staff from the Delta following a similar move by Shell.