Residents near Nigeria’s Brass facility – run by oil and gas company Eni – reported that a large oil spill has spread through the sea and swamps of the oil producing Niger Delta region.

According to the reports, oil from the plant has spread across the sea and swamps of the Niger Delta region. Eni has claimed it was not able to determine the cause of the spill.

The company was quoted by Reuters as saying that during loading operations on a tanker on 27 November, an oil spill in the sea was noticed.

"Operations were immediately suspended and resumed only after it was verified that the vessel’s structures were not damaged and were not leaking," the company commented.

Bayelsa Odioama fishing community chairman Francis Clinton Tubo Ikagi said he saw a thick layer of crude oil on the river.

"Our women and men whose main livelihood source is fishing are complaining bitterly to us that the whole river is full of oil," Tubo Ikagi said.

Nigerian legislators are planning to impose strict laws on operators responsible for oil spills, which would levy huge fines as a measure to reduce the frequency of such accidents.

In the last decade, Nigeria-based oil companies have been claiming that the majority of oil spills are caused by sabotage and theft of oil, but have failed to support their claims.

According to reports, most spills are caused by loading accidents or weak infrastructure, while theft and pipeline sabotage add to the problem.

In event of finding the company guilty, it is liable to fund the clean-up of each spill, as well as pay compensation to impacted communities. From January to September 2013, ENI has reported 471 spills in the Niger Delta, while Shell recorded 138 such cases, according to an Amnesty International report.