You have to look at the terms and conditions of the Airbnb contract you have with them.
You have to report them to Airbnb and also give them a notice to vacate.
The police will not get involved as it is a civil matter.
Once you give them the notice to vacate if the do not leave then you have to get a court order.
This is the process. You should also look at what your contract with Airbnb says about you being compensated in these circumstances from the management of Airbnb
But in Australia you have to sue to get them out.
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