India remained the most popular source of spam or junk mail in June while Brazil returned to second place with an increase of 4.4 percentage points compared to May, a new study has said.

According to Kaspersky Lab's spam report for June 2011, the most noteworthy changes saw South Korea fall from second to fourth in the rating that tracks where spam originates, while Russia dropped two places to seventh.

The volume of spam in mail traffic increased slightly compared to May and averaged 83.3 per cent. The most popular topics were Osama bin Laden's death, the last Harry Potter movie the anniversary of Michael Jackson's death, the report said.

Meanwhile, Japan was the latest world power to combat the distribution of unwanted emails at the legislative level. As of June, the creation, distribution, purchase and storage of malicious programs as well as the distribution of pornographic spam is a criminal offence in the country.

The amount of phishing emails remained unchanged and accounted for 0.02 per cent of all mail traffic. However, there was a considerable increase in the amount of phishing attacks on social networks Habbo and Facebook, increasing by 6.25 and 4.07 percentage points respectively, pushing the sites up to third and fourth places in the list of organisations attacked most.

The experts at Kaspersky Lab also predict a surge in spam linked to Google+ after recent signs that spammers have begun exploiting the growing interest in the new social network.

"We expect an increase in unsolicited emails exploiting the new Google social network. They will most likely contain both phishing links and malicious code," says Maria Namestnikova, Senior Spam Analyst at Kaspersky Lab. PayPal and eBay had the unenviable distinction of attracting most attention from phishers in June.