I'm not sure how common or if it has been an ongoing (known) issue here.
However I just got to know from my friend that he received a call from some telemarking or bank credit card telesales, to which they asked him for his bank account.
Unknowingly he gave his account number and he received a sum of money in his account [to which he is not aware as well, as he don't check his account 24/7] - later on he receives a call asking for a sum of money back.
He lodged a police report and was told this is a licensed money lender case or something of that sort. So with the electronic money transferred to his account, they have proof they lent him the money. One new smart way it seems to lend the money without the 'borrower' knowing they've 'borrowed'.
However true this case is, just take pre-caution yourself, if any unknown parties call you requesting for account number, do not give. Probably you can give them your Starhub account number so they pay for your bills instead (LOL, just kidding. Don't give any details at all.)
Kindly share your finding/experience if any.
Do not PM me. I'm not affiliated with Starhub in any way. Owner of Sony Xperia™ Z1 (w/ Cyanogen Mod 11); OPPO Find 7a (w/ Cyanogen Mod 11s)