INVESTIGATIONS are continuing into what caused a house fire on a mining claim at Goanna Flats Rd near Rubyvale yesterday.

Neighbours on near-by claims and residences raised the alarm at about midday when they witnessed numerous exploding LNG gas bottles fuelling a fierce fire that destroyed two structures and a campervan.

No one was injured in the blaze.

Fire crews from Emerald and the Gemfields attended the inferno, which threw up a plume of smoke that could be seen from more than 20km away on the Capricorn Hwy.

"We could see it as passed Fort Lagoon Rd," Queensland Fire and Rescue Service Emerald controller Logan McIntosh said.

"The Gemfields Rural Brigade was the first unit to arrive and I dare say they would have been confronted with a fairly fierce burning fire."

Captain McIntosh said his biggest concern upon arrival at the mining claim were the unpredictable and dangerous gas cylinders, as well as two drums containing an unidentifiable and extremely hot liquid.

"Gas cylinders can fly up to 200m in any direction when they explode."

QFRS Emerald controller Logan McIntosh

By mid-afternoon, at least five unexploded gas cylinders had been discovered.

"There are also some drums containing something we can't identify at this stage," Mr McIntosh said.

"We need to talk to the owner."