Firefighters and emergency services struggling to control a massive blaze that has broken out on a construction site on Macquarie Street in Sydney's CBD.
It's reported the fire started just before 8 am, near both Legal Grounds Cafe and Parliament House.
The flames can be seen from the street by panicked bystanders; one spoke to 9NEWS saying the entire building looked to be ablaze within five minutes.
Another eye-witness told Today, "It seems to have been started from some form of an electrical spark or something on the plastic mesh and as we all know, plastic, as soon as it catches, it just goes up," he said.
It's not known for sure what started the fire or if there have been any injuries.
Macquarie Street is entirely closed this morning due to the fire - traffic delays to be expected.
More on this story as it develops.