Goldfields laundromat fire being mopped up

Firefighters are unable to finish mopping up a laundromat fire in Western Australia's Goldfields region that began just after midnight due to safety concerns.

The blaze at the business on Burt Street in Boulder was out of control at about 1.45am.

It had been brought under control by 7.30am, but spot fires remained because firefighters could not enter the building due to structural concerns.

The building will be inspected by a structural engineer and deemed safe to enter before firefighters can finish mopping up, the Department of Fire and Emergency Services says.

In the meantime, they continue to hose the building to keep materials cool.

Police said the blaze was spotted by a security officer conducting patrols.

Guests at two nearby hotels were temporarily evacuated due to the potential danger.

It is believed the fire caused about $500,000 damage, but a more thorough assessment is yet to be made.