A “hazardous material” incident has unfolded at a building on a street in Melbourne’s CBD.
Emergency crews were called to the high-rise on William St just before 8am on Tuesday.
Those inside had reported diesel fuel flooding through the corridors of the building and dripping through ceilings.
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Fire crews found a diesel fuel line on level 21 had ruptured and was spilling more than 100 litres of the liquid.
Firefighters have contained the leak and are now working to clear the spill.
There were 160 people inside at the time and they were all evacuated.
There are no injuries reported.
All northbound lanes of Williams St have been closed between Flinders St and Flinders Ln until the scene is cleared.
The southbound lanes remain open and motorists can use Market St, Queen St or King St as alternatives.