Google's online video sharing service YouTube has become the subject of a hacker attack.
Hackers have exploited a vulnerability in the comments section claiming to redirect visitors to singer Justin Beiber's fan page, but instead sending them to explicit websites.
The attack on the teenage pop star has been credited to members of the infamous hacker forum 4chan.
The Next Web reports that visitors have been redirected to a number of different explicit videos, while another covers the screen with the words 'OMG Faggot'.
Some users have reported over Twitter that they have seen a banner claiming that Justin Beiber died in an 'horrific' car accident.
Security experts believe that hackers infiltrated YouTube by using malformed HTML scripts on the comments page.
Google has reacted by blocking the comments section and manually deleting the posts containing the malicious script.
In a statement to The Next Web, the company said: “Comments were temporarily hidden by default within an hour, and we released a complete fix for the issue in about two hours. We’re continuing to study the vulnerability to help prevent similar issues in the future.”