public static function removeUserFromGroups($uid)
	{
		$db = \App::get('db');
		$tables = array('#__xgroups_members', '#__xgroups_managers', '#__xgroups_invitees', '#__xgroups_applicants');

		foreach ($tables as $table)
		{
			$sql = "DELETE FROM `".$table."` WHERE uidNumber=" . $db->quote($uid);
			$db->setQuery($sql);
			$db->query();
		}

		return true;
	}