The Wall Street Journal reports:

The U.S. Air Force is blocking its personnel from using work computers to view the websites of the New York Times and other major publications that have posted classified diplomatic cables, people familiar with the matter said.

Air Force users who try to view the websites of the New York Times, Britain’s Guardian, Spain’s El Pais, France’s Le Monde or German magazine Der Spiegel instead get a page that says, “ACCESS DENIED. Internet Usage is Logged & Monitored,” according to a screen shot reviewed by The Wall Street Journal. The notice warns that anyone who accesses unauthorized sites from military computers could be punished.

The Air Force said it had blocked more than 25 websites that contained the documents, originally obtained by the website WikiLeaks and published starting late last month, in order to keep classified material off unclassified computer systems.

Major Toni Tones, a spokeswoman for Air Force Space Command, wouldn’t name the websites but said they might include media sites. Removing such material after it ends up on a computer could require “unnecessary time and resources,” Major Tones said.