Hackers are known to be online bullies with no rivals, but this week, The hacker collective known as Anonymous-the group that took over Burger King's Twitter account and claimed that the Whopper had been acquired by the home of Ronald McDonald,  was hacked this week by a rival group named Rustle League, reported Inquisitr.

Rustle League has worked with Anonymous before on "missions," though for whatever reason they decided to take over one of Anonymous' multiple accounts, @Anon_central, according to redorbit.com.

So what is the Rustle League? Vice.com reports that the hacking group, which consists of five main members, formed last Summer. They're all reportedly 20-somethings working in the online security industry who moonlight as professional internet trolls.

Jaime Cochran, co-chair of Rustle League, said:

"We see ourselves as the old Anonymous, which is more about having fun and fucking with people rather than revolution and saving the world. Although, what we do does serve a purpose in society," reported Inquisitr.

"The reason Anonymous fell victim is probably human weakness," explained security expert Graham Cluely with Sophos, speaking to the BBC. "Chances are that they followed poor password practices, like using the same password in multiple places or choosing a password that was easy to crack."

Adding, "Everyone should learn better password security from incidents like this - if it can happen to an account run by Anonymous supporters, it could happen to you."

Anonymous, however, laughed at the claim saying: "lol BBC, you will have to wait for a full story," reported Inquisitr. 

To fend off more online attacks and to save themselves from any legal issues, Twitter  encouraged users to take extreme care when choosing their passwords this week, noting, "there's been a fair amount of conversation about account security on Twitter" over the past few days, stated redorbit.com.

In a blog post, director of information security Bob Lord urges Twitter users to pick a strong password, avoid suspicious links, and keep your information to yourself rather than share it with unknown third parties. The same security suggestions can be used anywhere online. It's never prudent to click any link that looks suspicious, and it's always best to use different passwords for each account, rather than one password for every account you own, according to redorbit.com.