The phishing emails, claiming HM Revenue & Customs has reviewed the recipient's tax return and found they are due a refund, then asks for personal details, including credit card or banking details, saying they are required to make the refund.
However, HMRC officials said such emails are fake and HMRC never emails a taxpayer about a refund; those who are owed money receive payment by mail.
HMRC officials said 522 illegal sites sending out such messages were closed down in 2012.
The sites were hosted in a number of countries, officials said, including the United States, Russia and Japan, as well as countries in central and eastern Europe.
"HMRC do everything we can to ensure customers are safe online and we are working closely with other law enforcement agencies to target the criminals behind this serious crime," HMRC head of digital security Gareth Lloyd told The Guardian newspaper.