title: How can I delete Docker's images?
body: <p>I've the following images:</p>
  
  <pre><code>alex@alexvps:~$ sudo docker images
  REPOSITORY          TAG                 IMAGE ID            CREATED             VIRTUAL SIZE
  &lt;none&gt;              &lt;none&gt;              70c0e19168cf        5 days ago          1.069 GB
  &lt;none&gt;              &lt;none&gt;              c2ce80b62174        8 days ago          399.2 MB
  &lt;none&gt;              &lt;none&gt;              60afe4036d97        8 days ago          325.1 MB
  </code></pre>
  
  <p>and when I try to remove one of them I get:</p>
  
  <pre><code>alex@alexvps:~$ sudo docker rmi 60afe4036d97
  Error: Conflict, 60afe4036d97 wasn't deleted
  2014/01/28 00:54:00 Error: failed to remove one or more images
  </code></pre>
  
  <p>How can I remove them? Why is there such conflict?</p>