The anti-cheat team attempting to safeguard the Call of Duty franchise has confirmed that over 20,000 players were banned during the recent Modern Warfare II open beta.

The open beta was initially made available on PlayStation from September 18 to September 20, before being opened up to other platforms from September 24 to September 26.

According to Team Ricochet, the overseers of Activision's kernel-level anti-cheat system for the Call of Duty franchise, 72 percent of players detected to be cheating during the open beta were "actioned on before they ever played a single match."

"For those that were able to play normally (assuming every match they played included the use of cheats), our systems were able to detect and remove them from our ecosystem – on average – within five matches played," said the team in a blog post.

Team Ricochet said it also banned over 60,000 illicit accounts before they managed to access the event, so it seems like the open beta pulled in delinquents like moths to a flame. The team even called out some banned players for attempting to circumvent justice by claiming they were the victim of a bug related to beta crash reports.

"There were a small number of players who reported beta crashes that appeared to cause their accounts to be permanently banned," reads the post. "We have investigated this thoroughly and have determined that crashing issues did not cause unjust bans. The game itself cannot trigger a ban. Additionally, our security and data engineers have confirmed that there was not a bug possible which would have allowed this to happen during the beta."

There was one system that did unjustly impact players, however, with some users being kicked out of matches for friendly fire -- irrespective of whether it was intentional or accidental. Team Ricochet has assured players that problem has now been fixed, and that players won't be booted from games at launch for having an itchy trigger finger.

"While we certainly appreciate how much of a team player our security systems are, this issue only persisted for a short period on Sunday before being resolved. We are confident that we’ve addressed this for launch. Also, and just in general, don’t fire at your teammates," the blog continues.

Overall, Team Ricochet said the open beta was a success in terms of allowing it to hone its security systems, and described combating cheaters as an "ebb and flow process."

"The benefit of a pre-release beta is being able to test new methodologies and systems ahead of launch to see what is viable, as well as retain the full scope of Ricochet Anti-Cheat to keep our cards closer to our chest," added Team Ricochet.

"Combating cheaters is an ebb and flow process. There is no simple solution to stop cheating from ever occurring. While only partial anti-cheat systems were deployed for the free-to-play beta, the security team gained valuable learnings of what worked and what did not."