An employee for Hearst TV, who works in the building where the workers are trapped, has tweeted that the lower three floors have been evacuated in case the scaffold collapses.
More top news
Transport for London has revoked Uber's license in the capital.
ITV News understands the FA was told of a second separate investigation around Mark Sampson just months into his job as England head coach.
Metropolitan Police Commissioner Cressida Dick said the bomb could have caused deaths if it had fully detonated.