A dramatic crash involving a truck on SH1 south of Christchurch has blocked traffic.
Police were called to the collision on the rail overbridge north of the Rakaia River just before 2:30PM this afternoon.
A witness told Newshub the barrier had been ripped out by the crash and the truck was lying on its side.
The southbound lane is currently blocked, while northbound traffic is being diverted down North Rakaia Road.
Any motorists travelling southbound are advised to avoid the area if possible.