Since handguns are illegal, I think it's unfair to expect a high ranking policeman to know what one looks like, let alone use the correct term to describe it. Assuming it wasn't a spanner or a multi-tool, it could possibly be a handgun fitted with a sound suppressor or indeed a true silenced handgun like a Welrod, although they are extremely rare.
Obviously his desire to get before the cameras resulted in a very sloppy performance. Understandable in a tabloid journalist maybe, but inexcusable in a police officer.
Regards, Jon.