More than half a million users registered for the new social media site Gettr after its launch on Sunday, though the website was briefly hacked, founder Jason Miller told Reuters.

Several high profile alumni of the Trump administration were targeted by the hacker, who appears to be a pro-Palestinian activist. Miller, a senior adviser to former President Donald Trump, said the hacker was quickly detected and only managed to change the user names of several accounts.

"You know you're shaking things up when they come after you. The problem was detected and sealed in a matter of minutes, and all the intruder was able to accomplish was to change a few user names," Miller said in a statement to several media outlets. "The situation has been rectified and we've already had more than half a million users sign up for our exciting new platform!"

Zachary Petrizzo, a writer for Salon, posted several screenshots on Twitter showing how the accounts for former Secretary of State Mike Pompeo, Rep. Marjorie Taylor Green (R-Ga.), American Conservative Union Chairman Matt Schlapp, and Miller had their names changed by a hacker who identified himself by the Twitter handle "@JubaBaghdad."

According to timestamps exclusively reviewed by @Salon, the "Gettr" hack occurred around 10:10 AM EST and targeted… https://t.co/ZF6vXcEtPD

— Zachary Petrizzo (@ZTPetrizzo) 1625410256.0

According to Insider, the accounts for Steve Bannon, Harlan Hill, Sean Parnell, and Newsmax were also compromised Sunday morning.

These account's profiles were changed to read either "@JubaBaghdad was here :) ^^ free palestine ^^" or "@JubaBaghdad was here, follow me in twitter :)".

Insider contacted the Twitter account that claimed responsibility for the hack. @JubaBaghdad reportedly said he targeted the anti-cancel culture social media platform "just for fun" and that from a technical standpoint, it was "easy."

"They should not publish the website before making sure everything, or at least almost everything, is secure," the hacker told Insider.

Gettr, short for "Getting Together", is a Twitter-alternative social media website founded by former Trump campaign spokesmen Miller and Tim Murtaugh. The site was launched as a pro-free speech platform where users would not be de-platformed for sharing their political beliefs.

Like Twitter, users can micro-blog by sending messages that can contain up to 777 characters, as well as pictures or videos. The website was launched on July 4 to declare independence from "Big Tech social media oligarchs."

Trump has been absent from social media since he was permanently banned from Twitter and indefinitely suspended by Facebook and YouTube following the Jan. 6 riot at the U.S. Capitol. Though Gettr was founded by Trump campaign veterans and several high profile members of Trump world quickly joined, the former president is not involved and reportedly will not be joining the social network.