diff --git a/classes/observers/group_observer.php b/classes/observers/group_observer.php
index b7c7b78..535835b 100644
--- a/classes/observers/group_observer.php
+++ b/classes/observers/group_observer.php
@@ -51,4 +51,19 @@ public static function group_created(\core\event\group_created $event) {
             $DB->insert_record_raw('block_groups_hide', ['id' => $groupid], true, false, true);
         }
     }
+
+    /**
+     * Handles the group_deleted event.
+     * Automatically deletes the groups from the block_groups_hide table when a group itself has been deleted.
+     *
+     * @param \core\event\group_deleted $event
+     */
+    public static function group_deleted(\core\event\group_deleted $event) {
+        global $DB;
+
+        $groupid = $event->objectid;
+
+        // Remove the group from the block_groups_hide table.
+        $DB->delete_records('block_groups_hide', ['id' => $groupid]);
+    }
 }
diff --git a/db/events.php b/db/events.php
index 7d90229..fc279cc 100644
--- a/db/events.php
+++ b/db/events.php
@@ -29,4 +29,8 @@
         'eventname' => '\core\event\group_created',
         'callback' => '\block_groups\observers\group_observer::group_created',
     ],
+    [
+        'eventname' => '\core\event\group_deleted',
+        'callback' => '\block_groups\observers\group_observer::group_deleted',
+    ],
 ];