Panic swept through Bukavu in the Democratic Republic of the Congo on Saturday after M23 rebels entered the city in South Kivu province

People were seen fleeing in the morning, the World Food Programme said one of its warehouses was looted, and inmates from the city's main prison were freed.

Later, the streets fell quiet as residents braced for what is to come.

The rebels' self-proclaimed governor of Bukavu, Pierre Bahizi, called for calm.

"We must not leave power in the street," he said on Saturday.

The Congolese government and international observers have long accused neighboring Rwanda of backing the M23 rebels. Rwanda denies this.

"We are asking for one thing and cannot accept anything else: the withdrawal of Rwandan troops from Congolese territory," Congolese Prime Minister Judith Suminwa told the Reuters news agency on Saturday.

"We are an independent country and we must protect the integrity of our territory."

Guterres warns against escalation

The conflict in eastern Congo was a major topic of discussion at the African Union summit in Ethiopia on Saturday.

UN Secretary-General Antonio Guterres told the summit that escalation must be avoided at all costs and that there is no military solution.

"The fighting that is raging in South Kivu — as a result of the continuation of the M23 offensive — threatens to push the entire region over the precipice," Guterres said without mentioning Rwanda.

He called for "diplomacy and dialogue".

"And the sovereignty and territorial integrity of the DRC must be respected," Guterres added.

Edited by: Wesley Dockery