Drush php fatal error on clear cache all

Hi,

Using drush to clear the cache i have the following php error:

PHP Fatal error:  Class 'Symfony\Component\DependencyInjection\ContainerBuilder' not found in /var/www/drupal8/core/includes/bootstrap.inc on line 2430
PHP Fatal error:  Class 'Symfony\Component\DependencyInjection\ContainerBuilder' not found in /var/www/drupal8/core/includes/bootstrap.inc on line 2430