Following a cash-in-transit heist, the N6 Road between Stutterheim and East London re-opened for traffic at 2.30 am on Wednesday.
Hawks spokesperson Captain Yolisa Mgolodela says late on Tuesday, suspects fired shots at an armoured vehicle from G4S forcing it to stop.
She says the driver of the van was shot and injured before guards were robbed of three firearms.
The suspects bombed the van before intercepting the escort vehicle behind the truck.
Captain Mgolodela says a shootout ensued and two crew members from the escort vehicle were slightly injured.
According to Provincial Traffic, the suspects hijacked an articulated truck and used it to block one side of the road making it difficult for police to respond.
The suspects fled the scene with an undisclosed amount of cash and the truck's keys.
The scene took hours to clear as there were explosives on the scene.
