M23 rebels are trapped and they know it. So they make desperate moves:

DRC's M23 call for Zuma's help

We're requesting Zuma to speak to Kabila to stop the fatalities," said M23 spokesperson Lawrence Kingston in an interview with the Mail & Guardian.

"South Africa should stop sending military to Congo. He's got to help the Congolese people live side by side in peace instead of helping Kabila kill them."

South Africa sent troops to the DRC earlier in the year as part of the United Nations mission to neutralise armed groups in the country.
http://mg.co.za/article/2013-10-29-d...or-zumas-help/

they accuse Zuma to have business perspectives and interests in DRC... But so do they, as well as in Rwanda, and so do a lot of Rwandan.

US also published a statement:

Press Releases: Renewed Fighting in Eastern DRC
The United States is deeply concerned by reports of renewed fighting between the M23 armed group and the armed forces of the Democratic Republic of the Congo (DRC) in eastern Congo, with reports of casualties and of hundreds of families forced to flee the area of the fighting. We are also troubled by reports that at least one round landed across the border in Rwanda. This fighting puts at risk the fragile peace negotiations in Kampala and risks undermining the concerted efforts earlier this week to reach a final agreement and peacefully resolve the conflict. We commend the actions of the UN peacekeeping mission in the DRC (MONUSCO) to protect civilians and urgently call on all parties to exercise restraint to prevent military escalation of the conflict.

We specifically call on the M23 to commit to peacefully resolving the conflict by promptly signing a final agreement that provides for the disarmament and demobilization of the armed group and accountability for those responsible for the most serious human rights abuses. We commend the good faith efforts of the DRC government to negotiate a principled agreement and continue to call on all signatories of the Peace, Security, and Cooperation Framework to support such an agreement and to end all support to armed groups.

We continue to believe that the best way forward for the Great Lakes region is to conclude the Kampala Talks in a manner that does not grant amnesty to the worst offenders and to utilize the Framework peace process to focus on the root causes of the crisis in the DRC, including through expanded dialogue among signatory states.
http://www.newsroomamerica.com/story...stern_drc.html

But this will not work neither because calling rebels to sit at negotiation table to surrender and be accountable for the war crimes (at best, possible crimes against humanity after 2 mass graves have been found) they committed is not really an exit door option.