If you go to the post via viewtopic.php, you can click on the info button to get post details.
Then (mcp.php), you can edit the content, change the poster, lock the post to prevent any further editing (except by a moderator) or delete it. If you choose to erase the post, you can decide to actually remove the post from the database or just hide it from the normal users.
Finally, if you permanently delete the post, you'll eventually get an error message "The post you requested does not exist" instead of going back to a valid page (MCP for example). It's definitely a bug. That doesn't occur if you delete the post directly in the topic (viewtopic.php).