An Act to facilitate compliance by Australia with obligations under the Rome Statute of the International Criminal Court, and for related purposes
Part 6—Search, seizure and powers of arrest
Division 4—Arrest and related matters
131 Persons to be informed of grounds of arrest
A person who arrests another person under this Act or pursuant to a warrant issued under this Act must inform the other person, at the time of the arrest, of the crime in respect of which, or, if the other person is arrested under section 182, the reason for which, the other person is being arrested.
It is sufficient if the other person is informed of the substance of the crime or reason, and it is not necessary that this be done in language of a precise or technical nature.
Language
Fair trial standards
Rights during investigation - access to interpreter and translation if questioned in other language
Rights during investigation - informed of belief that crime has been committed
EDIT.