The UN secretary-general has fired the head of the UN peacekeeping mission in the Central African Republic over the force's handling of a series of misconduct allegations, including rape and killing.

Ban Ki-moon, speaking with unusual force, said on Wednesday he has accepted the resignation of Babacar Gaye of Senegal and declared, "Enough is enough." He called a special session of the UN Security Council for Thursday over the issue of sexual abuse allegations that has rocked the world body.

"I cannot put into words how anguished and angered and ashamed I am by recurrent reports over the years of reports of sex abuse and exploitation by UN forces," said Ban, who first heard about the latest allegations on Tuesday, a week after the first UN officials were informed. "I will not tolerate any action that causes people to replace trust with fear."