The United Nations says it is investigating new allegations of sexual exploitation and abuse by UN peacekeepers in violence-ridden Central African Republic.

A UN official said the allegations involve three underage girls. The allegations also involve two pregnancies, the official said, speaking on condition of anonymity because details have not been made public.

The UN peacekeeping mission in Central African Republic said in a statement that it learned of the new allegations Wednesday and will send a team to the location on Thursday "to gather the facts, sensitize the troops involved, and to take immediate preventive and disciplinary measures."

The United Nations is already investigating at least 16 other cases of possible sexual misconduct by UN troops and police in the country, where the force has been active since September 2014. A series of earlier allegations led Secretary-General Ban Ki-moon in August to take the unprecedented step of asking the head of the peacekeeping mission to resign.

Wednesday's statement cited the new head of the peacekeeping mission, Parfait Onanga-Anyanga, as calling any single incident of abuse "utterly abhorrent," and it said he pledged "to ensure justice is served in each and every case."

The statement gave few details about the latest allegations, including the ages of the underage girls and where in Central African Republic the alleged abuse occurred. It also does not say what country or countries the peacekeepers are from.

The mission in Central African Republic currently has more than 9,300 troops and more than 1,800 police trying to calm deadly violence between Christians and Muslims. Hundreds more UN peacekeepers are expected to arrive before the country's transitional government holds elections next month.

The UN chief has acknowledged the persistent problem of sexual abuse and exploitation among peacekeepers, saying earlier this year the issues was "one of my greatest disappointments." He announced a series of reforms, including his intention to repatriate the troops of countries that don't act on allegations.

The UN has no standing army and relies on countries, largely African and South Asian ones, to contribute troops and police in return for monthly payments. The UN has more than 105,000 troops and police in 16 missions in some of the world's most dangerous places.