This week, how criminals have created hundreds of fake websites designed to trick people into thinking they are owned by big banks such as HSBC and NatWest.
How does it work?
The internet is awash with more than 300 fake websites designed to look like they are run by respected high street banks, according to research from online security company Domain Tools.
Its researchers discovered a total of 110 fake HSBC sites, 74 for each Barclays and Standard Chartered, 66 for NatWest and 22 for Lloyds.
The dodgy addresses, which are all owned by third parties, all have marked similarities to the banks' real websites and include hsbc-direct.com, barclaya.net, barclays-supports.com and lloydstsbs.com.
Anyone visiting them by mistake can be tricked into passing their account information to the fraudsters behind the sites.
Cyber criminals can also use sites of this kind to download malicious software onto visitors' devices.
How can I avoid being caught out?
Ways to spot a fake bank website include checking for extra letters or dashes in the addresses.
You should also watch out for plural or singular versions of the correct domain name - such as barclay.com rather than barclays.com - and for reversed letters.
HSBC.com, for example, could become HBSC.com on a fraudulent site.
I've been defrauded. What should I do?
The first thing to do if you think you have fallen for a fake website is to contact your bank to ensure your accounts are secure and change any passwords or login details that may have been compromised.
Informing the bank about the dodgy site will also enable it to take action to protect other customers, as will reporting the fraud to Action Fraud (0300 123 2040).