An oil spill at an ExxonMobil facility offshore from the Niger Delta has spread at least 20 miles from its source, coating waters used by fishermen in a film of sludge.
Exxon officials did not immediately respond to a request of Reuters for comment.
Exxon said last week it had shut a pipeline off the coast of Akwa Ibom State after an oil leak whose cause was unknown.
"This is the worst spill in this community since Exxon started its operations in the area," said Edet Asuquo, 40, a fisherman in the Mkpanak community, as women scooped oil into buckets. In some marshy areas, green plants were poking out of the slick, not yet dead and blackened by the newly arrived oil.
"The fishermen cannot fish any longer and have no alternative means of survival," Asuquo said.
The U.S. major's outage comes on top of multiple production problems in Nigeria after fellow oil majors Shell and Eni reported recent disruptions at onshore sites due to oil theft and Nigeria's worst flooding in 50 years.
One fisherman described noticing a large quantity of oil on the surface of the seas and all over the beach penultimate Friday, adding that the company has since sprayed chemicals in the water which was helping disperse it.
It was the second major oil spill near Exxon facilities in three months. At the end of August, an oil spill left a slick running for miles along the coast.
A United Nations. report in August last year criticised the government and multinational oil firms for 50 years of oil pollution that has devastated the Ogoniland region, and some communities are attempting to sue for compensation in Western courts.
"Our prayers are for tough punishment on the oil companies operating the Niger Delta," said secretary of the fishermen's association Inyang Ekong, as the car he was in swept past oil washing up onto beaches in an area called Ibeno.