Investigators will probe whether private school boys used a TikTok 'deodorant bomb' to start a once-in-a-decade fire in Sydney.
The seven-storey building on Randle Street in Surry Hills erupted into flames last Thursday, with almost 120 firefighters called to fight the towering blaze.
On Tuesday, NSW Police confirmed investigators had spoken to four boys about the incident but are yet to lay any charges.
2GB's Ben Fordham said the arson squad was investigating whether the fire was started by an aerosol can.
He said he had received a tip from concerned parents of a friend of one of the boys allegedly involved in the incident late on Tuesday.
'It's one of those crazy crazes that has spread on social media,' he said.
'I've seen a video online, it's been made by a kid teaching others how to make a deodorant bomb, I'm not going to describe how it's made.
'Apparently deodorant bombs are a bit of a thing. The deodorant bomb is dangerous enough, but when you add a flame to it, you can only imagine the result.'
Fordham said the kids involved in the fire were 'devastated' about what's happened.
'They come from good families, they go to nice schools, they live around the eastern suburbs. And at least one of them goes to school just a block away from the vacant building that burnt to the ground.'
The host said that boy had been inside the building before the fire erupted and had taken a photo inside and posted it on social media.
More to come.