Index: src/wp-admin/includes/ms.php
===================================================================
--- src/wp-admin/includes/ms.php	(revision 26302)
+++ src/wp-admin/includes/ms.php	(working copy)
@@ -148,6 +148,15 @@
 		}
 
 		clean_blog_cache( $blog );
+
+		/**
+		 * Fires after the site is deleted from the network.
+		 *
+		 * @since 3.8.0
+		 *
+		 * @param int $blog_id ID of the site that was deleted from the network.
+		 */
+		do_action( 'deleted_site', $blog_id );
 	}
 
 	if ( $switch )