NSW scrap yard fire put out after 18 hours

A fire at a scrap metal yard in Sydney's west has been extinguished after firefighters battled for 18 hours to put it out.

Crews have been working since Monday evening when the huge fire ripped through the Tattersal Road site in Kings Park.

Firefighters used a large excavator to pull apart the scrap metal, which was about 15-metres high, Supt Greg Rankin from Fire and Rescue NSW said on Tuesday.

No injuries were reported but nearby residents and business-owners were told to avoid the area due to lingering smoke.

Investigators are still determining what caused the blaze but it's not believed to be suspicious.