GENEVA (Reuters) - U.N. investigators of war atrocities in South Sudan urged the African Union (AU) on Tuesday to make a final push to secure justice for millions of victims.

Oil-rich South Sudan gained independence from Sudan in 2011 but slid into civil war in December 2013, with President Salva Kiir’s army battling rebels under his ex-deputy Riek Machar.

Under a 2015 peace deal that fell apart in 2016, the AU and South Sudan were supposed to set up a “hybrid court” consisting of South Sudanese and other African judges, to try people accused of atrocities. But the court has yet to be created.

“The hybrid court of South Sudan is but a signature away. The African Union needs to act with great urgency,” Yasmin Sooka, chair of the Commission on Human Rights in South Sudan, told the 47 member states of the rights council in Geneva.

The court was an African solution to an African problem, Sooka said, but the AU had told her that they were waiting for South Sudan to designate a government official to sign a memorandum of understanding on the court.

“Once that has happened, then the path is free to set up the court immediately. Once that has been done, a prosecutor can be appointed, judges can be designated, and the rules of procedure can begin to be formalized,” she said.

Sooka’s team has identified more than 40 South Sudanese military officers who may be responsible for war crimes and crimes against humanity.

South Sudanese Justice Minister Paulino Wanawilla Unango told the Council that Sooka’s report was generalized and flawed.

“There is actually improvement in the security and human rights situation,” he said, without mentioning the memorandum.

He said there had been 203 cases against members of the army for serious crimes including murder and rape, and some had been jailed. “It is not true that there is impunity and (that) there is not any kind of accountability.”

Sooka warned in late 2016 of a “Rwanda-like” genocide and said rape was taking place “on an epic scale” in South Sudan. Although talk of genocide has subsided, Sooka said barbarities were continuing and she provided some graphic testimony.

“A mother had her eyes gouged out with spears as she tried in vain to prevent her 17-year old daughter from being raped by 14 soldiers,” she told the Council.

“After being blinded, she herself was raped by 17 soldiers. Her husband was later found by his son, beheaded and castrated, with his penis stuffed in his mouth,” Sooka said.