The N2 in Cape Town was closed early on Tuesday following a cash-in-transit heist overnight.
Provincial traffic chief Kenny Africa said the N2 was closed between the M9 at Macassar and Baden Powell Drive inbound.
The fidelity vehicle which was attacked was still at the crime scene in the morning.
Africa said the N2 incoming left lane remained closed but the right lane had been opened.
Western Cape police could not immediately comment.