Aftermath: The scene outside the Russell Street side of the Galleria Shopping Centre in Morley after the explosion. Credit:James Mooney "We will be fully co-operating with all the relevant authorities in their investigations and will be conducting our own investigation. "Our focus at this moment is supporting those injured people and their families and our other employees." It was revealed on Tuesday afternoon that a second man had died in Royal Perth Hospital as a result of injuries sustained in the explosion. The blast occurred inside the shopping centre some time around 9.30am near the Woolworths loading bay area on Russell Street.

Jonathan McDonagh, who was among the first people at the scene, told Radio 6PR he saw three people running from the building and a puff of smoke but did not hear an explosion. "As I came driving into the Galleria I (have) seen one guy coming running out and he was on fire," he said. "And I (have) seen two guys coming out from the same door and they were on fire. And I knew straight away what was happening. "The first fella came running out and he was lying on the ground in the shade and he was the one I was putting out. "There was another lad lying on the ground and two other boys lying on the ground. One of them was dead.

"The other fella was getting put out by other people. I was running back and forth trying to put one person out at a time. "When I seen (the) man was out and there was no more flames anymore and he was not breathing... I had to leave after seeing it." The cause of the explosion is unknown but lightning has been ruled out in the wake of a severe electrical storm overnight. Police said it was believed all four men were working in an area near an electrical transformer.

Stephen Beer from centre manager Federation Centres said the accident occurred during routine electrical maintenance. At the scene, Police Inspector Rob Harrison had earlier confirmed the death of one person, while St John Ambulance area manager Murray Allum said three people had been taken to Royal Perth Hospital with serious burns and another was taken to Queen Elizabeth II medical centre suffering smoke inhalation. Mr Allum said the most serious of those who'd been taken to hospital had received burns to about 80 per cent of the body. Radio 6PR's Danica De Giorgio reported two of the people taken to RPH had burns to 60 per cent of their bodies. A spokeswoman from the hospital confirmed another two people involved in the incident were currently in a critical condition.

Earlier, Channel Seven reporter Amelia Broun told Radio 6PR it was a "pretty horrific scene" following the incident just after 9.30am. She said a witness described seeing four men running out of the doors, burning head to toe and screaming for help. "The witnesses we spoke to said they were very badly burned and that it was hard to tell whether they were in uniform or members of the public," she said. Channel Nine reporter Oliver Peterson told Radio 6PR that emergency services had rushed to the scene. "They're blocking people off around the car park, keeping them 10 to 15 metres away," he said.

"It's a door that would come into the carpark... it might be a staff entry around the back. "There are dozens of fire trucks and ambulances on the scene here at Morley Galleria. It is thought the incident happened near a loading bay near Woolworths in Russell Street." The shopping centre is still open but part of the centre did lose power for a short period after the initial explosion. A spokesperson for Woolworths said the supermarket had been evacuated. "It did not occur in the Woolworths store or areas managed by Woolworths," she said.

"Our thoughts are with those injured in the incident. Unfortunately we understand WA Police have confirmed there has been a fatality and our thoughts are with family and friends." DFES said a structural fire was reported at 9.38am. Police said some roads around Galleria have been closed. - with AAP Follow WAtoday on Twitter