Apex Legends has postponed the North America finals for its Global Series championship over concerns that hackers have compromised the “competitive integrity” of the game. Two professional players from major teams were targeted while livestreaming on Sunday by an attack that forcibly applied advantage-granting cheats during competitive gameplay.

The cause of these attacks hasn’t been officially verified, leading to speculation that the hack may have been delivered via Apex Legend’s anti-cheat protections. An exchange posted by a cheat monitoring account on X claims that the attacker found an RCE, or remote code execution, exploit to run their code directly on the players’ computers.

Two posts from accounts that say they represent Epic Online Services and Easy Anti-Cheat have tweeted messages saying, “…we are confident that there is no RCE vulnerability within EAC being exploited.”

Late Tuesday night, more than two days after the incident, Respawn’s account on X tweeted a message confirming “a few” pro accounts were hacked during the event and that “Our teams have deployed the first of a layered series of updates to protect the Apex Legends player community and create a secure experience for everyone.”

There were no details on whether or not player’s computers could be hacked, or any information about mitigations against attacks on systems or accounts. The account for Apex Legends Esports also said in a post, “We are still actively working with our partners at EA and Respawn and remain committed to ensuring the security and competitive integrity of Apex Legends tournaments. At this time, we do not anticipate any changes to the Split 1 Playoffs. We will have more information to share on the Challenger Circuit and the NA Regional Finals soon.”

A Twitch clip of DarkZero’s Noyan “Genburten” Ozkose shows a UI interface for aimbot software appearing on his screen, at the same moment that a message reading “Apex hacking global series by Destroyer2009 & R4ndom” begins repeatedly spamming chat. “I’m getting hacked,” Genburten said, while raising his hands to show he was no longer in control. Genburten noticed he could see other players through walls and promptly abandoned the match.

TSM’s Phillip “ImperialHal” Dosen was also targeted, with admins shutting down the game lobby after the player realized an aimbot had been applied to his account. While not much is known about “R4ndom” — one of the two aliases mentioned during Genburten’s hack — “Destroyer2009” is recognized for previous questionable activity targeting Apex Legends players like ImperialHal and Mande.

Update March 18th, 10:14PM ET: Added tweets from Epic / Easy Anti-Cheat.

Update March 20th, 12:26AM ET: Added information from Respawn / Apex Legends Esports.