Microsoft is filing lawsuits against more than 50 Europeans as part of a crackdown on phishing scammers.
The software company said it had managed to get ISPs which host phishing websites to hand over information so it can identify the people behind them.
Four UK nationals are to face legal action, which could include "formal complaints, action in court and settlements against serious criminals", the company said.
Neil Holloway, Microsoft's European president, said: "If we live in a world where the internet is not safe to the user, they are less likely to use the technology."
He denied that the lawsuits are part of a publicity move to boost the company's image. "I don't think it's a about branding but about making sure our customers have a secure experience," he said.
Law firm Olswang is acting for Microsoft in the four UK lawsuits but has not named the individuals or the ISP involved.
Microsoft is taking action against 20 people in Turkey, 10 in France, seven in Spain, four in Morocco, four in the UK, four in Germany and one each in Austria, Egypt and Sweden.
The company said it will launch another 50 lawsuits by the end of June.
Microsoft said the move is part of its Global Phishing Enforcement Initiative, which it launched in Brussels on Monday.
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