How is this attack conducted? In this particular case, users were lured to the site using various Twitter messages. The messages of the tweets varied: some said the site was interesting, while others explicitly warned users not to click on it.
Twitter posts leading to “browser crasher” page
Pop-up on iPhone
The message in Japanese tells users that they will not be able to get off the page, no matter what they do. Clicking the OK button will not be enough to get rid of the pop-up, as a new one will appear with exactly the same message. This pop-up will keep bothering the user and stop them from using the browser until they are able to get off the offending page.