Children believed to have lit blaze that tore through Brisbane construction site

Four children are believed to be responsible for lighting a blaze that tore through a north Brisbane construction site.

The four youths were spotted on surveillance cameras, entering the building in Chermside just after six o'clock last night.

It's believed they set fire to sheets of shade cloth that were covering the scaffolding.

The fire ripped through the top level and spread to the middle of the building.

Firefighters arrived just before 7am and were able to bring the fire under control within minutes, thanks to working fire hydrants inside the building.

No one was hurt in the blaze.

Police are investigating and construction workers have been sent home for the day.