JOHANNESBURG—South Africa deployed soldiers on Monday to quell violence that erupted in the wake of former president Jacob Zuma’s jailing, after days of riots left at least six people dead. Police said disturbances had intensified and 219 people were arrested as the controversial ex-leader challenged his 15-month prison term in the country’s top court. Smoke from burning buildings swirled in the air as items from burgled shops lay strewn by the side of the road in Pietermaritzburg in Zuma’s home province of KwaZulu-Natal (KZN). The sporadic pro-Zuma protests that broke out when he handed himself over last week have quickly escalated into looting and arson, mainly in KZN but also in Gauteng where the biggest city Johannesburg is. Opportunistic criminals appear to be taking advantage of the anger some feel over Zuma’s incarceration to steal and cause destruction, police said. A statement from the military said “pre-deployment processes had started” …