Deputy President David Mabuza is pushing ahead with his defamation case against a Mpumalanga businessman who accused him of being behind political killings in the province. Mabuza’s lawyer, Ulrich Roux says the case will be heard in the Mbombela High Court today. The country’s second-in-command is seeking relief from the court for a cost order against a former ANC member, Pompie Letwaba.