Any user in the dialog’s occupant_ids is able to remove a message from the dialog. The message will only be removed for the current user. The message will still be viewable in the chat history for all other users in the dialog.
You may be wondering why this request only deletes the message for the current user. It is to allow deletion functionality within your app and ensure the message does not reappear in the user chat history, but without affecting the history of other users.
It is possible to completely remove a message by the owner - pass force=1.