Giant machines to work on Northern Line extension

Two machines the length of football pitches which will create the first major Tube line extension since the 90's will be unveiled today.

It is a significant milestone in the expansion of the Northern line that is set to create 24,000 new jobs and 18,000 new homes in Vauxhall, Nine Elms and Battersea.

Credit: Nick Ansell/PA Wire/PA Images