In this June 20, 2010 file photo, men walk in an oil slick covering a creek near Bodo City in the oil-rich Niger Delta region of Nigeria. (Photo by Sunday Alamba/AP)

Multiple bombings on Agip oil pipelines in the Niger Delta, an oil-rich region of southern Nigeria, have caused thousands of barrels of crude to seep into rivers and farmlands.

Eke-Spiff Erempagamo, a community leader in the southern Bayelsa state characterized the spill as "massive — the biggest in years," according to the Associated Press.

A spokesperson for AGIP's parent company, Italian multinational oil giant ENI, said that 16,000 barrels of oil have been lost per day since the attacks occurred on Thursday and Friday, totaling at least 48,000 lost barrels of oil. Production was immediately shut off following the attacks, but resumed on Monday.

'Oil pollution drives impoverished communities deeper into poverty.'

The Niger Delta has struggled to mitigate the environmental impact caused by frequent pipeline leaks and spills along the region's sprawling infrastructure. Amnesty International found last year that Royal Dutch Shell and ENI had admitted to over 550 oil spills in the Niger Delta in 2014, compared to just ten spills across the whole of Europe between 1971 and 2011.

"In any other country, this would be a national emergency," Audrey Gaughran, the group's global issues director, said at the time of the report. "In Nigeria it appears to be a standard operating procedure for the oil industry. The human cost is horrific — people living with pollution every day of their lives."

The report noted that companies vastly underreported the extent of spills, saying leaks totaled only 30,000 barrels. Amnesty, however, said "given the very poor reporting systems used by oil companies, this figure is highly likely to be a significant underestimate."

Joe Westby, who focuses on oil and gas issues in Nigeria for Amnesty International, said the amount of oil spilled in the region over the weekend was "shocking."

Westby said the people most likely to be affected are low-income farmers and fisherman, who are almost entirely dependent on the environment for their livelihoods. "Oil pollution drives impoverished communities deeper into poverty," Westby said. "A big part of the problem is that the oil is never cleaned up fast enough."

Oil companies are expected to initiate their own clean ups, regardless of what causes a spill. Westby said that oil company clean up efforts are often a matter of too little, too late. "The process is completely ineffective" Westby said. "The environment remains polluted, and then continues to disrupt and devastate peoples lives, sometimes for decades. It's really a tragic situation."

Earlier this month, Shell agreed to an $84 million settlement following a pipeline that burst twice in 2008. Internal documents obtained by Amnesty International found that Shell had repeatedly ignored suggestions to replace outdated pipe. Lawyers representing the 15,600 Nigerian fisherman affected reported that their clients will receive $3,300 for their losses from the spills, some of which were caused by leaks, and others allegedly caused by oil theft.

Following a preliminary investigation into Thursday's attack, Israel Sunny-Goli, a member of the Bayelsa state assembly condemned the attack on the Agip pipeline. "This is a clear sabotage by economic saboteurs" Sunny-Goli told Reuters.

The recent attacks have sparked concerns that an old conflict may be returning. Until an amnesty agreement in 2009, rebels operating under the umbrella group The Movement for the Emancipation of the Niger Delta (MEND) regularly attacked oil and gas facilities and kidnapped oil sector workers. Rebels ceded their weapons in exchange for unconditional pardons in 2009. At the time, over 1,000 people per year were dying due to the conflict, which had reducing Nigeria's oil production by 40 percent.

Former oil kingpin and MEND leader Government Ekpemupolo, also known as Tompolo, is suspected to be behind the attacks. Nigerian authorities issued a warrant for Tompolo's arrest in January after he failed to appear in court to face corruption charges. Tompolo's media aide Paul Bebenimibo has since shrugged off any suggestion that his client had a hand in the bombings.

Tensions have been bubbling up in the southern region ever since Nigeria's new president, Muhammadu Buhari, swept to victory last year on promises to tackle systemic corruption.

Rebels benefited from the 2009 amnesty program, often signing lucrative pipeline protection agreements, which included education and vocational training. Buhari recently agreed to extend the program for another year, after previously threatening to cancel it.