A new oil spill at a Shell facility has contaminated farmland and a river, upending livelihoods in fishing and farming communities in parts of the Niger Delta, which has long endured environmental pollution caused by oil industry players.

The National Oil Spill Detection and Response Agency (NOSDRA) said the spill came from the Trans-Niger Pipeline operated by Shell, which passes through communities in Eleme area of Ogoni land, a region where the London-based energy giant has faced decades-long local pushback to its oil exploration.

The volume of oil spilled has not been determined, but activists have published images of polluted farmland, water surfaces blighted by oil sheens and dead fish mired in sticky crude.

While spills are frequent in the region due to vandalism by oil thieves and lack of pipelines maintenance, according to the United Nations (UN) Environmental Programme (UNDP), activists call this a major one.

An environmental activist, whose non-profit monitors spills in the region, Fyneface Dumnamene, said: “This is one of the worst in the last 16 years in Ogoni land, It began on June 11.

“It lasted for over a week, bursts into Okulu River, which adjoins other rivers, and ultimately empties into the Atlantic Ocean, affecting several communities and displacing more than 300 fishers.”

He said tides have sent oil sheens about 10 kilometers (6 miles) further to creeks near the nation’s oil business capital, Port Harcourt.

Shell stopped production in Ogoni land more than 20 years ago amid deadly unrest from residents protesting environmental damage, but the Trans-Niger Pipeline still sends crude from oil fields in other areas through the region’s communities to export terminals.

The leak has been contained, but treating the fallout from the spill at farms and the Okulu River, which runs through communities, has stalled, NOSDRA Director General Idris Musa said.

He added that response has been delayed, blaming protesting residents. He, however, noted that engagement is ongoing.