White supremacists are taking a beating online from hacker groups.

On Saturday, hackers from the groups Anonymous and Binarysec shut down the website of the White Knights of the KKK using a distributed denial-of-service attack, according to Mic. The shutdown came on the same day "pro-white" demonstrators staged a rally in Stone Mountain, Georgia, a historic meeting place for the Klan.

White supremacist groups are on the rise in the U.S., according to an analysis from the Southern Poverty Law Center. The number of KKK chapters nationwide grew from 72 to 190 in 2015, bringing total active membership to between 5,000 and 8,000. Republican presidential front-runner Donald Trump's racist and xenophobic remarks on the campaign trail have buoyed the white supremacist movement, according to Mark Potok, a senior fellow at the SPLC.

"Trump’s demonizing statements about Latinos and Muslims have electrified the radical right, leading to glowing endorsements from white nationalist leaders such as Jared Taylor and former Klansman David Duke," Potok wrote in February. "White supremacist forums are awash with electoral joy, having dubbed Trump their 'Glorious Leader.'"

While inflammatory statements and public rallies get the most press coverage, more and more of the Klan's activities are happening online. The neo-Nazi website Stormfront, which Anonymous has targeted in the past, has more than 300,000 members and is growing steadily, according to the SPLC.

Anonymous' attack on Saturday was the latest in a series of offensives against online white supremacist communities that hacker groups are calling #OpKKK. In November, hackers released the private information of hundreds of alleged KKK members online.

Hackers say they're fighting back against an "evil" organization.

"Part of OpKKK is bringing attention to the fact that these groups are not dead are in fact finding a new life online," a Binarysec hacker, who uses the online handle Zombie Ghost, said in an interview, according to the International Business Times.

As of early Wednesday afternoon, the White Knights of the KKK site was still offline.