UPDATE: Volunteer firefighters who tackled the Perth Hills fire last weekend are devastated by extensive damage caused by vandals who targeted their emergency services complex.
Thieves broke into the Gosnells State Emergency Service unit about 3.30am today, setting fire to cars and causing damage to the building.
The deliberately lit fire destroyed two cars - a KIA and a BMW - that had been impounded.
Police were called to the complex on Canning Park Avenue in Maddington in response to a passerby's report that vehicles had been set alight.
It is understood that the burnt cars had been parked at the front of the complex because the carpark was full.
The offenders forced their way into an adjacent building and stole items including a "pocket rocket" motorcycle and a laptop.
It is believed that the offenders cut through an electric fence to gain access to the centre, before making their way inside the building and punching a hole through a door.
They also smashed a glass fridge door that contained alcohol.
"Some thoughtless individuals broke in to the Gosnells Emergency Operation Centre used by both the Gosnells SES and Gosnells Bush Fire Brigade," Gosnells SES said this afternoon.
"Initially it was thought that they had only set fire to some impounded vehicles being stored in the carpark on behalf of Gosnells.
"Upon further investigation, it appears that they took equipment from trucks and used it to break in to the Emergency Operations Centre.
"They smashed their way through doors and, once inside, it appears they broke into drawers and cabinets."
Gosnells SES local manager Paul Hollamby said the volunteers were devastated that their ability to respond to emergency situations in their community had been affected.
"Some of the members have been volunteering in the community for 35 years and helped raise funds for the construction of the Emergency Operations Centre," Mr Hollamby said.
"The volunteers and their families gave up their personal time so that the volunteers would have somewhere to train, store equipment and respond to emergencies."
"This thoughtless act will affect the commitment of the emergency service volunteers.
"They will re-think their willingness because, next time, these vandals may steal or damage their personal vehicles and property of the volunteers."
Mr Hollamby said the Gosnells volunteers had collectively worn orange "for more than 8000 hours across the State last year while helping to respond to and prepare for disasters".
He said the unit's volunteers had been overwhelmed by offers of support from other SES teams.
"These same volunteers spent hundreds of man hours assisting at the recent fires at Parkerville," Mr Hollamby said.
"It is immensely disappointing for volunteers when they realise there are people in the community who prey on them while they assist other community members."
Rangers were at the scene this morning with City of Gosnells representatives and Mayor Dave Griffiths.
Mr Griffiths expressed his concern for making sure that the station would be able to continue responding to emergencies despite the break-in.
"There was a break-in at the council depot and the fire vehicles were tampered with," Mr Griffiths said.
"They broke into various points on the property and they broke into the volunteers' room, where they smashed the beer fridge and drank some beers.
"My great concern was that with this terrible fire season, we can respond to any emergency that comes along.
"Because the vehicles couldn't be used until the [police] forensics went through them, we couldn't go anywhere, but we did cover our bases in the case that there was an emergency."
Mr Griffiths said it was disgusting that the offenders did not consider the hot weather and fires when they decided to cause a ruckus at the complex.
He said everything possible was being done to find out who the offenders were and that there were a number leads that could help solve the investigation.
Anyone with information about the crime is asked to call Crime Stoppers on 1800 333 000.