Boot any comment bot that fills in the author website field

_tw_intercept_comment.php

<?php
/**
 * Boot any comment bot that fills in the author website field.
 */
function _tw_intercept_comment( array $data ){
    if( empty($data['comment_author_url']) ){
        return $data;
    }
    get_header();
    echo 'See ya';
    get_footer();
    exit(0);
} 

add_filter('preprocess_comment','_tw_intercept_comment');