Can you see if this works?
RewriteEngine On
RewriteBase /DIRECTORY/AID/
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-l
^news/([A-Za-z0-9_]+)$ news.php?id=$1 [QSA,L]
EDIT : Fixed the regex character class definitions.