Tens of thousands of Nigerian fishermen and farmers are suing multinational oil giant Shell in two new lawsuits in a British court alleging decades of uncleaned oil spills have destroyed their lives.

Law firm Leigh Day & Co. is representing them following a landmark ruling in the same UK court last year that won an unprecedented $83.5 million in damages from Shell. Shell originally offered a settlement of $50,000.

Shell in a statement blamed sabotage and oil theft for the pollution and said it will challenge the jurisdiction of the British court.

Nigeria's oil-rich southern Niger Delta suffers hundreds of spills every year. Typically, victims spend years battling in Nigeria's court system only to come away with a small amount, so lawyers took the battle to Shell's London headquarters.