Police are investigating the cause of the fire that tore through Leading Edge Computers in the early hours of Tuesday morning.

Owner Blake Casper did not know the full extent of the damage on Tuesday afternoon, but said he was “in shock”.

Close to 30 firefighters battled to control the blaze that appears to have started at the back of the store. 

It threatened nearby buildings – including Federation University facilities – and took 40 minutes for firefighters to control. 

Ballarat City Fire Station operations Officer Anthony Pearce said a rapid response from Ballarat City, Ballarat and Wendouree crews prevented the fire from spreading. He said the major priority for crews had been to contain and extinguish the flames.

Firefighters were initially called to the store, at the corner of Grant and Armstrong streets at 2.40am. 

Mr Casper said he would not know the full impact of the blaze on the business until later in the week.

“We still sort of have to figure out what we will do. We haven't had access to the site as investigations are continuing,” Mr Casper said. 

Mr Pearce said fire investigators were looking into the cause of the fire with police but had not yet determined the cause of the blaze. 

Firefighters remained at the scene of the fire until about 9am. 

“Fire investigators will work with police to determine the cause (of the blaze),” Mr Pearce said.

“The fire did do more significant damage at the rear end of the building.” 

Ballarat City Fire Brigade incident controller Scott Gambino said there was significant damage and smoke in the area. 

"There was significant damage, about 70 per cent of the store was destroyed by fire. What was not burnt was damaged by smoke and water."

Mr Casper said the store had been located at the site for two years.

“The shock is only just starting to wear off. We were supposed to re-open (after a break) on Wednesday,” Mr Casper said.

Mr Casper said the store would not re-open until the new Year. Anyone with orders should visit the Leading Edge Computers Facebook page.