Up to 120 Australian Tax Office and Australian Securities and Investment Commission investigators yesterday raided 13 Melbourne and Brisbane offices and homes as part of a major investigation into corrupt bankruptcy businesses.

The investigation centres on so-called Phoenix schemes where businesses go bankrupt to avoid paying debts, including tax and workers entitlements.

ATO Deputy Commissioner Michael Cranston. Credit:Rob Homer

"These visits are part of an ongoing investigation into the activities of a firm of pre-insolvency advisors and their involvement in encouraging and facilitating illegal phoenix activity, evading GST and failing to pay tax on $22 million of unreported income," ATO Deputy Commissioner Michael Cranston said.

"By showing up unannounced we're able to access records that we might otherwise never have seen."