Six people have been taken to hospital after an 12-car pile-up on the Pacific Motorway in Brisbane's south.
The crash occurred about 6am in northbound lanes near the Juliette Street off ramp on the motorway at Greenslopes.
Five ambulance crews were called to the scene.
No-one was seriously injured but six people were transported to hospital in a stable condition with seven other patients assessed at the scene.
There were delays until about 11am, when police said the roadway had been completely cleared.
Queensland Police Senior Sergeant Todd Sucic said all lanes were closed for "20 to 25 minutes" but one lane was opened around 6:30am.
He said all the cars in the initial crash were "significantly damaged", while multiple other minor crashes also occurred around the incident.
"There was one major traffic accident, which involved 11 vehicles," he said.
"There were a few minor traffic accidents, unfortunately, around the peripheral on the Pacific Motorway and the on-ramps."
'The only word for it is chaotic'
Michael Garrahy from the Queensland Ambulance Service said six vehicles and paramedics were able to quickly assess the 13 patients involved.
"We classify this as a mass casualty incident where the amount of patients outweighs the amount of resources," he said.
"The only word for it is chaotic.
"We're very lucky due to the high skill of our critical care paramedics, they were able to clear those patients quite quickly and we realised we've got minor-to-low injuries so we can slow down and look on patients."
Cause of crash unclear
Senior Sergeant Sucic said it would take some time to figure out what caused the crash.
"What I've been told by our first response officers, the speed limit of the vehicles were travelling at that time was roughly 90 to 100 [kilometres per hour]," he said.
"For whatever reason, there was a sudden drop in traffic — your guess is as good as mine.
"We are extremely lucky that we walked away with no fatalities."
He said more information would come from an investigation into the incident.
"We will be interviewing everyone involved," he said.
"It might take us a while but we'll get there."
