Screenshot by Laura Hautala / CNET

Has Donald Trump awakened a mighty giant?

The vigilante hacking collective Anonymous -- known for attacking ISIS, the Westboro Baptist Church and agricultural biotech giant Monsanto -- said Friday it is targeting Donald Trump, the leading Republican contender for president of the United States. Shortly after the proclamation, the website for the candidate's New York Trump Tower reportedly went offline.

A representative for Anonymous, speaking in a YouTube video, said the hackers targeted Trump because he proposed banning Muslims from entering the country, a policy position that drew condemnation and controversy throughout the week.

Trump's statements and policy positions up to now have inspired outrage, blog posts and memes, all of which have become standard fare in American politics.

Now, Anonymous has turned its hacking resources toward publicly attacking a presidential contender.

The Trump campaign did not respond to a phone message and an email requesting comment. CloudFare, a security company named on the Trump Tower website, declined to confirm whether the building website uses its software. The website is back up, after being down for about an hour.

If the reports of Anonymous' success are true, then Trump joins a high-profile list of targets. Anonymous also launched a campaign against ISIS, the Islamic militant group that claimed responsibility for the Paris attacks last month. So far, it has taken credit for shutting down several ISIS Twitter accounts and defacing its online propaganda sites.

Overall, Anonymous' impact on its targets is hard to gauge. ISIS is still an influential presence online, including on Twitter. And other companies trying to stamp out terrorist activity on the Internet have found it challenging.

Trump, like ISIS, receives outsized attention for his savvy use of social media. It remains to be seen whether Anonymous will have any lasting impact on either.