Oil prices increased drastically on Wednesday amidst violence in Nigeria and a warning that the Organization of the Petroleum Exporting Countries (OPEC) may not be able to meet its share of global oil demand by 2024, the Associated Press reported. The concerns for rising oil prices, which have now reached around $100 a barrel on supply, came after armed men invaded Port Harcourt, the center of Nigeria's oil industry on Tuesday. The armed men attacked two police stations and raided the lobby of a major hotel-four policemen, three civilians and six attackers were killed. The Niger Delta Vigilante Movement claimed responsibility for the attack. “Although the violence has not impacted oil flow out of the country, it has reignited supply concerns as militant attacks have reduced Nigeria's crude output by roughly 20 percent since 2006,” said John Gerdes, an analyst at SunTrust Robinson Humphrey in a research note. Amidst the violence in Nigeria, OPEC said that its member nations may not be able to meet demand as early as 2024, though OPEC also said that deadline could slide for decades if members increase oil production more quickly.