Penrith supplement shop destroyed in 'suspicious' blaze

A fire which destroyed a supplement shop in western Sydney overnight is being treated as suspicious.

Fire crews were called to the store in Coreen Ave, Penrith, about 11.30pm following reports of a shop on fire.

NSW Fire and Rescue crews arrived at the scene and brought the fire under control before it spread to neighbouring businesses.

No one was injured but a crime scene was established, with investigators sifting through the smouldering remains of the property this morning.

Superintendent Graham Jarrett said nine crews and 40 firefighters were called in to tackle the blaze.

"It was fantastic work by the firies to stop it spreading," he told reporters.

"There is a fairly large gas cylinder out the front, and again it was good work by them to stop it becoming involved.

Supt Jarrett said the situation could have been much more dangerous if the gas cylinder caught on fire.

He said fire investigators would work with police to work out sparked the fire.

Anyone with information should call Crime Stoppers on 1800 333 000.