The setup often involves luring investors into various stocks via online chat groups, which then initially rise in price. The scammers then sell at a profit while those who remain see the stocks fall in price.
This is a type of manipulation that we have seen before, but we have seen several major cases recently, says Malin Alpen, acting director-general of the Financial Supervisory Authority.
The method is also called "pump and dump" - where the scammer pumps up the stock price and then sells at a profit.
This is a way in which criminal actors exploit the financial system for criminal purposes. It is of course illegal and very unfortunate, says Alpen.
"Be wary if you are contacted by someone you do not know who gives you stock tips, even if the person appears to be a well-known profile", says Peter Hallström, senior finance inspector at the Financial Supervisory Authority, in a written comment.
If it sounds too good to be true, it probably is.
