Hazeyview - Three security officers were shot and wounded in a cash-in-transit heist between Mkhuhlu and Cunningmoore, in Mpumalanga on Tuesday, police and paramedics said.The SBV guards were transporting money to Ximhungwe Spar when a grey Mercedes E-Class crashed into them and forced them to a stop around 09:00, Captain Phillip Sakude said.The occupants of the Mercedes opened fire on the guards. When the guards refused to open the van, they used explosives to blow open the roof.The suspects entered the vehicle and shot and wounded three of the guards. One was in a critical condition, while the rest sustained moderate to minor injuries, Netcare 911 spokesperson Athlenda Mathe said. A fourth security guard was treated for teargas inhalation. Sakude said the guards shot two of the robbers, but they managed to flee in a Toyota Fortuner, black BMW, and a white Mercedes, with an undisclosed amount of money. Police found a number of R5 cartridges on the scene. No arrests had yet been made.