Such scams are rampant now; I recently suffered a similar fate. As I tried to use the BP cash point along Woolwich road few Saturdays ago, the terminal started playing up after I had entered my pin and the amount I wanted to withdraw. I was lucky that my cousin was with me, I had asked him to keep watch from the car while I went inside to complain to the attendants. By the time I came back, my cousin said that the two black boys who had stood behind me as I was attempting to make the withdrawal, and who were ‘too friendly' when I was having problems with the terminal and ‘encouraged' me to go away and phone the bank had actually come back, this time in a car and were heading towards the cash point when they suddenly saw my cousin again and they screeched off.
My brother, I don't know which magic they do at cash points these days but I have since learnt not to withdraw cash from outside cash points. I try now to use ones inside the bank where CCTV scares the scammers from rigging the cash points.
The £250 I wanted to withdraw left my account but when I complained, Barclays refunded it.