“The fire occurred at an illegal bunkering site situated on the border between Rivers State and Imo State,” the Nigerian Civil Defense and Security Corps (NSCDC) said in a statement sent to CNN on Sunday.
It said the fire had caused “the deaths of hundreds of men, women and children”, adding that the remains of some victims “were burned beyond recognition”.
According to local media reports, emergency response teams have counted 109 bodies, while others are still missing.
In October last year, 25 people, including children, were killed in an explosion at an illegal refinery in Rivers State, one of Nigeria’s main oil-producing areas.
Oil theft and artisanal crude refining is a common practice in the delta region of the country. The practice is to boil crude oil to extract fuel that contributes to pollution in the region.
Government figures released last year and reported by Nigerian media revealed that more than 400,000 barrels of crude oil are lost to theft every day.