Whakatane explosions heard 11km away

The scene of Friday night's blaze. PHOTO/SUPPLIED

A fire investigator, WorkSafe NZ staff and police remain at the scene of a fire that sent explosions rocketing through Whakatane last night.

One half of the Pohutu St building where the blaze was centred was used to store plumbing equipment and what looked like close to 100 gas cylinders of varying sizes.

The cylinders appeared to be closer to the rear of the building.

Whakatane Rockgas has its premises only metres from where the fire blazed but its building escaped unscathed.

However the timber and corrugated iron back section of the building storing the gas bottles was destroyed with the front section looking like it had been badly damaged by smoke.

Up to six fire trucks from throughout the Eastern Bay went to the 9.30pm fire including crews from Edgecumbe. One of the Edgecumbe volunteers said the crew had heard one of the explosions as they left their station - more than 11km away.

Otakiri resident Kris Byrne said she had also heard the largest of the explosions from her home.

Firefighters battling the blaze from the service lane running directly behind the building said the corrugated iron walls of the building fell as they worked to contain the flames.

Parts of the building were still burning at 4.30am. The building was finally entered at 6am.

A man with a workshop close to building, and who did not want to be named, said bits of charred iron appeared to have been blasted over the roof of a neighbouring building and were strewn on the ground.

He pointed out a large dent with a hole near the top of a nearby two-storey building and said it looked like something had gone "shooting" through the wall.

The Rotorua Daily Post understands that while many of the gas cylinders were empty, they has been used to contain a variety of gases including LPG, oxygen, nitrogen, CO2, helium and acetylene. Also housed in the shed were two huge canisters used to store a product for reducing frost damage in orchards.

It is also believed two vehicles were in the shed.

One of the firefighters, who did not want to be named, said the fire had the potential to do considerable damage if it had not been contained.