// Tree provider

CMS.TreeEngine.TreeProvider provider = new CMS.TreeEngine.TreeProvider(CMS.CMSHelper.CMSContext.CurrentUser);

// Get document with specified site, aliaspath and culture

CMS.TreeEngine.TreeNode node = provider.SelectSingleNode(CMS.CMSHelper.CMSContext.CurrentSiteName, "/News/MyFirstNews", "en-us");

if (node != null)

{

  // Delete the document

  node.Delete();

}