Forums Scripts & Popups Detecting "knocks" in remote scripts

Sometimes I need to change the mode of my channel to 'invited' in order to prevent troll attacks. We get "Knock <UserName> invite only" notifies whenever someone tries to enter and I am going to write a script that can respond to this notifies.

However, I couldn't find any remote event about these types of messages (in other words, I don't know what they are classified as).

Thanks in advance!