Street art in Cheltenham, near GCHQ, attributed to Banksy (Matt Cardy/Getty Images)

Sharp-eyed techies and hipsters in Shoreditch may have noticed some new pavement ads this week.

But the tagging isn't an invitation to a cafe that only serves kimchi-topped baked potatoes or a blog launch.

It's a recruitment ad for government intelligence agency GCHQ:

The temporary 'reverse' graffiti is created by cleaning away street dirt.

The ads read:

GCH-WHO? Technical Opportunities GCHQ-Careers.co.uk

Business Insider reporter James Cook tweeted pictures of the ads in and around Old Street, London's tech hub, on Tuesday:

GCHQ confirmed in an email that the ads are a genuine attempt to get London's tech talent to swap start-up life for the bright lights of, umm, Cheltenham.

GCHQ's press office told i100.co.uk that the agency is experimenting with more "innovative ways of reaching the people we would like to recruit" and is using a range of channels to broaden its reach.