Health and safety was non-existent in the immediate aftermath of the CTV Building rescue mission, with firefighters being held by their ankles as they buried into makeshift tunnels to pull out survivors and corpses.
A coroner's inquest today heard from a senior search and rescue expert who described the "chaos" at the disaster site when he arrived two hours after the building's collapse.
David Berry, who led the Urban Search and Rescue (USAR) operation on the western side of the site, spoke of the incredible bravery shown by police officers, firefighters and civilian helpers who scrambled on top of the pancaked building trying to rescue survivors from the rubble.
A horizontal tunnel had been started, burying into the twisted steel and concrete, to drag out victims - alive and dead.
Firefighters were being held by their ankles trying to reach people as aftershocks continued to rock the rubble.
"It was very dangerous," he said.
The tunnel was narrow as well as "hot, smoky and dark", with the smell of burning corpses, and he could hear people crying for help.
"It was pretty ugly," he said.
Mr Berry, an experienced USAR specialist who was involved in the aftermath of the Pike River mining disaster, was speaking on day five of an inquest into the deaths of eight students who could not be saved from the wreckage of the CTV Building.
The USAR hazmat officer - senior station officer at Sockburn fire station in Christchurch - also talked the inquest through a horrifying amputation of one trapped survivor's leg.
The male Japanese victim's leg was trapped in the rubble.
It was so badly crushed that it was only around 1cm high, Mr Berry said.
Three times he climbed into the tunnel, which was becoming increasingly smoky.
The victim even offered him his oxygen mask at one point: "I didn't take it," he said today.
A decision was taken to amputate the man's crushed leg in a desperate bid to save his life.
The amputation took 15 to 20 minutes and he was then dragged clear and rushed off for medical help.
USAR has been criticised this week by other first responders, including police officers first on the scene, that once they showed up, the rescue operation slowed down.
Mr Berry admitted communication was poor on site. He didn't have a radio and had to rely on runners to communicate with a colleague who was leading the USAR rescue on the east side of the building.
"It was not particularly effective," he admitted.
He didn't believe he was in control of the whole site, and said there should have been a senior executive fire officer in overall charge.
The inquest is looking into the deaths of Tamara Cvetanova of Serbia, Cheng Mai of China, Japan's Rika Hyuga and Jessie Redouble, Emmabelle Anoba, Ezra Medalle, Reah Sumalpong and Mary Amantillo, all from the Philippines.
All were students at King's Education School for English Language on the CTV Building's third floor when the magnitude-6.3 shake struck at 12.51pm on February 22, 2011.
The tremor brought down the six-storey CTV Building resulting in the deaths of 115 people.
All eight survived the collapse but could not be rescued from the wreckage.
The inquest, before Coroner Gordon Matenga, continues.