A 21-year-old man has died and a workmate has been seriously injured when two floors of a Melbourne building site collapsed, dropping them about 15 metres to the ground.
Police say the men were working on the second floor of the Caulfield South site when it gave way, crashing to the first floor.
The first floor then collapsed and the men toppled to the ground.
Emergency crews and passersby worked frantically to remove building material from on top of the men.
The young man died at the scene, while a 48-year-old man was taken to The Alfred Hospital in a serious condition.
Nick Love, 21, was walking past when a police officer appealed for help.
He said he worked for more than 10 minutes helping pull a pile of wood off the two men.
The first man they reached was alive, he said.
"Once we got to the other guy he was under a lot of stuff and I just stepped back and let the paramedics jump in there," he told reporters.
A Metropolitan Fire Brigade spokesman said the building was to house a shop on the ground floor and two floors of apartments on top.
He said the men were installing the second storey flooring which had been delivered on Thursday morning.
An Ambulance Victoria spokeswoman said the surviving man suffered fractures to both his arms and possibly one of his legs.
"He has got serious injuries, but he was conscious and talking to us the whole time," she said.
Worksafe has investigators at the Hawthorn Road site and said a comprehensive investigation into the circumstances surrounding the incident was underway.
The man's death takes the number of workplace fatalities in Victoria so far this year to 11.
