In a statement published on the Bohemia Interactive website, the developer confirms that it has temporarily shut down access to its forums in response to an "illegal attempt" to access users' information.
"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," writes the developer.
"Please note due to the encryption of the passwords it is very unlikely that anything nefarious can be done with this information," adds Bohemia.
"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."
In response to the hacking attempt, Bohemia has reset the passwords of its registered users "as a precaution."