FOS\UserBundle\Model\UserManagerInterface::deleteUser PHP Method

    function deleteUser(UserInterface $user);

 /**
  * Removes the given user object.
  *
  * @param DataEvent $event
  */
 public function deleteObject(DataEvent $event)
 {
     $object = $event->getData();
     if ($object instanceof UserInterface) {
         $this->userManager->deleteUser($object);
         $this->eventDispatcher->dispatch(Events::POST_DELETE, $event);
         $event->stopPropagation();
     }
 }