UN Secretary General Ban Ki-moon has expressed serious concerns about renewed fighting in South Sudan despite a peace agreement earlier signed between the Juba government troops and rebels.

Ban said Friday that he was “deeply alarmed” by the ongoing fighting in South Sudan’s capital of Juba, blaming both sides for their “lack of commitment to the peace process.”

He further voiced concerns that the renewed violence was spreading to other regions of the world’s newest sovereign state, “which could lead to the dramatic deterioration of the security situation across the country.”

The South Sudanese people have suffered “unfathomable atrocities,” added the UN secretary general.

On Friday, some 200 people were forced to seek refuge at a UN compound following the eruption of armed violence among various groups in the western town of Wau.

In a separate incident, gunfire erupted near the presidential palace in Juba a day after five soldiers were killed during clashes between government troops and rebels.

South Sudan’s President Salva Kiir and his deputy, former rebel leader and Vice President Riek Machar, were both preparing to address the media at the compound when artillery fire broke out outside for nearly 30 minutes.

Machar’s spokesman James Gatdet Dak, meanwhile, issued a statement saying, “the heavy fighting which erupted... has subsided.”

“The two leaders are calling for calm, hopefully there will be calm,” he said.

The new clashes erupted just as the nascent nation is about to mark its fifth anniversary of independence from Sudan on Saturday.

The fresh wave of violence came despite the peace deal signed in August 2015 between Kiir and Machar.

Tens of thousands of people have died in South Sudan during more than two years of civil war, and nearly three million have been forced from their homes while five million survive on emergency food rations.

The country is also struggling with an economic crisis with a collapsing currency and the inflation spiraling out of control as its core oil industry is in tatters.