Bohemia Interactive has warned its community that their personal information may have been compromised after the developer's website was hacked.
"We have unfortunately discovered that an illegal attempt has been made to access certain of our online websites, leading to the download of a database containing usernames, email addresses and encrypted passwords. Please note due to the encryption of the passwords it is very unlikely that anything nefarious can be done with this information," Bohemia Interactive said in a statement.
"We would like to reassure everyone that no other information such as credit card details is stored by us and thus was not at any risk from this illegal breach."
It is now in the process of resetting user passwords and emailing users to request they choose a new password.
Bohemia Interactive is the studio behind the Arma series of combat games.