"There was what looked to be a Crown moving van with a trailer and a silver wreck which was completely totalled," she said.
"The ambulance staff were working on someone extensively. I was thankful I couldn't see great detail of who or what they were working on but there were people on the overpass craning over."
The witness said it appeared a northbound vehicle may have clipped a vehicle in the southbound lane.
"I know the speed at that time of day is pretty slow moving going south, but the northbound lane tends to be able to go faster in the morning," she said.
"It was surprising to see that in central Wellington because you don't usually have speeds where you would have that kind of car damage."
Motorists travelling into the city face lengthy delays, with traffic banked up past The terrace offramp. Image / NZTA
UPDATE 8:05AM Due to this crash, the Terrace Tunnel is CLOSED in both directions. Please use an alternative route and expect significant delays. ^EW https://t.co/tRCZ6PY4kb
