Some BS about tax "avoidation" (really!) and a summons about to be issued. "Call us back on this same no. to discuss it." They imply that they are the ATO, but all calls from the ATO always display "Private Caller", so it's clearly bogus. It's scammers trying to steal your money. Be aware!

Caller: Fake ATO scammer

Fake ATO scammer called to say I would be arrested

Caller: ATO scam (02) 8091 7678

ATO scam, rang on the mobile with a recording when we called back an indian accent male answered with hello this is the ATO whgen questioned he hung up

Caller: Some Indian scammer

Recorded broken message about being arrested for tax avoidance. I rang the number back and a male with an Indian answered "Australian Tax Office" I informed him that I had a missed call and he asked if I received a recorded message. When I said yes, he terminated the call.
No doubt a scam. I tried to call back several times and finally left a colourful message

Caller: Scam Call

Fake ATO scammer called to say I would be arrested due to about a tax debt, press 1 to make payment or return call using redial

Caller: (02) 8091 7678

Very similar to the descriptions above 1) pre-recorded message, 2) claiming Arrest warrant for Tax errors, 3) Press 1 or call back. I called back, call was answered immediately (just like the real Tax office, haha). ESL speaker on the phone. Hung up immediately. 99% sure it's a scam.

Something about a tax debt, press 1 to make payment or return call using redial