The protest marches occurred in cities like Melbourne, Sydney, Brisbane and Perth.

The protest marches were organized by Uni Students for Climate Justice.

New South Wales police told CNN more than 30,000 people attended the climate change protest in Sydney. Organizers put the number between 50,000 and 60,000 people.

"The bushfires are devastating communities and our government is not doing enough to stop it," Ambrose Hayes, 14, told CNN at a rally in Sydney. "The Morrison government needs to act before it's too late, before we reach a tipping point, before these impacts get worse than they already are."

Australian PM Scott Morrison has faced heavy criticism for his climate policies and response to the fires. Several of Friday's protests are under the slogan 'Sack Scomo', reported CNN. 

Speaking on their rally, the Uni Students for Climate Justice said in a Facebook post: "We're protesting this Friday because we're outraged about our government's criminal negligence about the bushfire crisis, exacerbated by climate change. We are protesting to give a voice to the tens of thousands of people who want real action on climate change and real funding for relief services." 

Australia is hit by worst bushfire incidents in recent times as the tragedy has claimed 27 lives so far, media reports said.