A cholera outbreak in Nigeria's northeast has killed dozens of people and led to hundreds of new infections, the United Nations said Saturday.

The disease first broke out in volatile Borno state two weeks ago. Cases were then reported in neighboring Yobe state.

"The cumulative number of recorded cases in both states currently stands at 3,126 including 97 deaths," the UN Office for the Coordination of Humanitarian Affairs (OCHA) said in a statement.

Nigeria's northeast experiences frequent attacks staged by extremist group Boko Haram, which has been waging a jihadi insurgency in the region since 2009. The UN added that the violence was hampering authorities' efforts to contain the outbreak.

Read more: Zimbabwe struggles to contain cholera outbreak

Crisis in Lake Chad area

Boko Haram militants said earlier this week they had executed a female health worker abducted from a UN-run health facility in Borno. The group also threatened to kill two other kidnapped health workers if the government did not meet its demands.

Read more: Islamist extremists overrun key Nigerian town

The Lake Chad area, which straddles parts of Nigeria, Cameroon, Chad and Niger, has also been hit by cholera. On Wednesday, the UN reported that more than 500 people there had died of the disease since the start of the year. It warned that more than 6 million could be affected if the outbreak wasn't brought under control.

Cholera is mostly spread by contaminated food or drinking water. It can cause severe diarrhea and vomiting, with the elderly, children and the sick most at risk.

Read more: Cholera epidemic in Yemen now affects 1 million people

nm/jm (AFP, dpa)

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