QUEENSLANDERS are being warned to remain vigilant after a spate of Christmas holiday scams using fake social media messages and emails.

Facebook messages appearing to be from victims' friends outlining how they can win competitions or secure government grants are the latest version of "upfront fee" fraud, police said.

A Queensland Police Media spokesman said this is the latest version of the "Advanced Fee Fraud" because you will be required to pay an upfront fee for tax or processing to obtain this so called "free" money.

Other versions of this scam are designed to trick you into giving over personal information by clicking on a link and asking for bank details, dates of birth, your address and other personal details.

Cybercrime detectives have also identified an increasing number of random emails containing terrifying threats designed to frighten people into handing over their money, which should also be deleted.

What you should do if you receive any type of extortion email:

Delete the email immediately. These messages are sent at random, so they won't know if they have reached a live email address or number unless you respond.

Do not respond to these emails. If you do, the scammers will escalate their intimidation and attempts to get your money.

Never send details or personal information to anyone you don't know or trust.

Use spam filters and be cautious when opening emails, especially if there are attachments.

If you are concerned for your safety, contact the police immediately.