public function deleteMark(Mark $mark)
    {
        $this->om->remove($mark);
        $this->om->flush();
        // First of all update older mark events so as result would be 0
        $this->updateNewMarkEventResult($mark->getUser(), $mark->getId(), 0);
        // Then delete mark
        $deleteMarkEvent = new LogResultsDeleteMarkEvent($mark);
        $this->dispatcher->dispatch('log', $deleteMarkEvent);
    }