Armed NYPD officer
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How NYPD has evolved to face terror threat post-9/11

Security correspondent Gordon Corera has had special access to the New York Police Department to see how they have changed the way they deal with terror threats in the years after the 11 September 2001 attacks on the World Trade Center.

Watch Gordon Corera and Steve Swann's reports on the NYPD in the post-9/11 era on the News at 10 on BBC One and Newsnight on BBC Two at 10.30pm.