The African Union should take steps to form a hybrid court in South Sudan that would investigate war crimes and violations of international law before valuable evidence is lost, more than 30 organizations said in an open letter.

The letter laid out a framework that would begin to hold individuals accountable for their actions in South Sudan’s civil war.

“Commitments at the state level in South Sudan and at the continental level in the African Union Peace and Security Council provide ample authority for the (African Union) to move ahead with the,” hybrid court, the letter said.

Under South Sudan’s peace agreement that was signed in August 2015, a hybrid court of South Sudanese and international judges are due to investigate violations of international law and South Sudanese law during its civil war.

But since signing the agreement, there has been little progress and the letter urged the African Union to take the first steps.

The letter urged the African Union to prepare the rules for the hybrid court so it would be created, and immediately create a way to preserve evidence.

“Evidence of crimes under international law is being lost or destroyed on a daily basis in South Sudan and it is vital that an official body be deployed to catalogue this information,” the statement said.

In June, President Salva Kiir was listed as author of an article in the New York Times that urged the international community to forgo global justice. In September, the government committed to the hybrid court again.