Christchurch police have laid charges against a householder they say submitted false invoices to the Earthquake Commission.
In a second case, police say a contractor is being investigated over invoices that appear to contain exaggerated figures.
Detective Senior Sergeant John Rae says the cases arise from complaints by EQC.
Mr Rae says a woman has been charged with obtaining an advantage by false pretences which carries a maximum penalty of seven years' jail.
It is alleged the woman faked invoices, indicating that she had paid them before seeking reimbursement from EQC.
The second case involving a contractor is still being investigated.
Mr Rae says the cases are the first of their kind relating to the Canterbury earthquakes, but expects more will follow.
Listen to Checkpoint interview with John Rae