Building is being evacuated…

Westminster cleared of people and traffic after major security scare around Parliament pic.twitter.com/Ym5pNIHiSW

— Jordan Newell (@jordannewell) November 17, 2014

UPDATE: False alarm:

An exciting start to my apprentice's first day at Parliament: the whole of Portcullis House evacuated cos of security scare over his iPad!

— Nick Boles (@NickBolesMP) November 17, 2014