This morning my brother received a call from his bank querying an irregular transaction on his bank account. As it turns out, yesterday he used his card in Melbourne and a few hours later in Bali (not possible given it takes 6 hours to get to Bali).
The bank advised that his card has been skimmed and have now placed a stop on the card. My brother has not been in Bali since Oct last year and whether the card was skimmed in Melbourne or Bali is debatable - however given the regular trips he has to Bali does make you wonder.
The bank is prepared to re-instate the funds, however first he must write a letter advising that he is in Melbourne and has not been in Bali recently. He now has the inconvenience of having to wait for a new card to arrive - which if you were in Bali could put you in a compromising position if all your funds are in one account - would suggest always take two different cards to be on the safe side.
I have attached a link below that shows what to look out for on an ATM and how to protect yourself from having your card skimmed.