The theft of their mail has cost one Selwyn couple $15,000 in a spate of incidents in recent months.
The district has been plagued by mail thefts dating back to last year when arrests were made in October and November.
However the problem has not been solved. One couple lost a $15,000 chequebook sent in the mail. The theives then used the couple's information to scam money from them.
Rolleston constable Liz Johnson said the mailbox was probably raided in December but the loss was not discovered until the couple realised the new chequebook was overdue.
The cheques inside totalled $15,000.