The BGT offices on Hill St were broken into twice over the weekend.

On Saturday night the chief executive officer's office was broken into and his laptop stolen.

On Sunday night the thieves returned, breaking in through the glass doors at the side of the building.

They caused extensive damage to the ceiling of a training room, ripping out two data-projectors worth an estimated $2500 each.

They also attempted to take a plasma TV from the wall but were unsuccessful.

Staff were shocked to see the state of the room when they arrived for work this morning, with insulation strewn across the floor and large ceiling panels broken into pieces.

BGT CEO David Edwards said the break in could affect more than 150 people scheduled to undertake training in the room during the week.

"They have been very specific in what they wanted,'' Mr Edwards said.

"The implications of this are ongoing.

"We'll have to either cancel or move the training scheduled.''

The two data projectors were only installed last June when the building was renovated.

Ballarat Police are currently at the scene.

More to come.