Big news today in terms of battling botnets:

Spanish authorities have taken down one of the world’s largest botnets, and have arrested three of the alleged masterminds behind it.

According to reports, the botnet – known as Mariposa (Spanish for ‘butterfly’) – is believed to have infected more than 13 million PCs in nearly 200 countries, and was found to be made up of computers inside over half of the Fortune 1,000 companies as well as more than 40 major banks.

More arrests are expected to come soon in other countries, the AP reports.