This question was asked on the financial stack exchange. The basic premise is that someone is giving another individual 'their' account number and telling the individual to take money out of it to pay his bills.
What most likely is happening is the individual giving the account number is giving someone else's account (which they stole) to the man, and will later ask the may to send back some of the money due to some made up excuse for needing to pay some emergency, thus the man is the one that takes money that isn't his (and will be forced to pay it back), while the fraudulent individual gets the man's money 'clean' that they can keep.
If I was in this situation my instinct would be to take the account information, then contact the bank in question and inform them that I suspect the account may be compromised, so they can contact the actual owner and arrange to change the account number to prevent the fraudulent individual from getting money out of the account.
I'm wondering if one was to do this would they be opening themselves up to potential legal trouble, perhaps for having access to another individuals account number when the owner of the account didn't intentionally give it to you?
I'm not sure where the asker of the question lives, but for the sake of the question assume the individual and bank are both located within the US.