It's worth stressing that there is absolutely no suggestion that Tesco or Twitter have been involved in any dishonesty.
ReportsAccording to a report on the This Is Money website, customers were asked to pass on their phone numbers so that customer care representatives (complete fakes in this case) could call. They would then attempt to get confidential details like passwords.
Tesco's genuine Twitter address is @UKTesco.
It's not known whether anyone fell for this. Graham Cluley, senior technology consultant at security specialist Sophos, told AOL Money: "There isn't any easy way to calculate how many people fall for fake Twitter accounts, unfortunately, but clearly quite a few people do get duped. This fake account seems to have been set up maliciously - but there have been plenty of others which have been more mischievous in the past." He pointed to the fake Wendi Deng Murdoch account that fooled a lot of people including News International itself as an example.
The usual rules apply to staying safe on a Twitter account or anything else like it. Don't click links. Anyone asking for your password in full is probably a fake. And if you think your bank may genuinely be trying to get hold of you, phone them directly rather than get a number from a Twitter link.
Blogger Guy Clapperton is the author of the book "This Is Social Commerce", published this week by Capstone.