Well known con at the moment - Surprised it was an Indian accenct as most of the gangs operating it seem to be east European. Couple of things you can do to keep them off other peoples backs for a while if you have time.

1. Tell them you will just put them on hold while you log on. Then keep them held until they get fed up.

2. Tell them you are doing exactly what they say but do nothing of the sort and just keep asking stupid questions.

3. Keep a very loud whistle or airhorn by the side of the phone...

DeG