Large industrial fire breaks out in Sydney’s north-west

A large fire has broken out in Sydney’s north-west, sending massive plumes of smoke into the air.

Video footage seen by nine.com.au shows a large building, believed to be a workshop on Loftus Street in Riverstone, engulfed in flames, with black smoke billowing into the air.

Fire crews are on the scene, and Fire and Rescue NSW told nine.com.au the fire has been contained to the building.

There were 12 firetrucks and about 40 firefighters who responded to the fire.

Paramedics were also called on the scene about 11.25am, where they told nine.com.au they were treating three patients.

Their condition is not known.

Nine.com.au understands the fire is not deemed to be suspicious, and may have stemmed from a mechanical issue.

Police have closed surrounding roads in the area.

More to come.