Police are warning computer users to take extra steps to protect their personal files from computer fraudsters.
The warning came after the National Fraud Intelligence Bureau received a number of reports relating to malicious software known as CryptoLocker.
The virus is mainly spread through email attachments and can take over personal files such as images and documents.
After the scam software has been downloaded on to a computer, a pop-up page will launch asking for a payment to remove it.
Detective Constable Julie Wheeldon, from the East Midlands Fraud and Financial Investigation Unit, said: “Malicious software, such as CryptoLocker, can be destructive but thankfully there are simple steps you can take to prevent yourself from becoming a victim.
“Installing security software on your computer and ensuring that you discard any emails from unknown addresses without opening them are two of the ways you can protect yourself against this type of fraud.”