Police prepare for mass riots at Thatcher's funeral in biggest security operation since the Olympics

Baroness Thatcher will be laid to rest amidst one of the biggest security operations in London's history

Police are preparing to carry out the biggest security operation in London since last year's Olympics

A ring of steel is being erected in London this afternoon in preparation for Margaret Thatcher's funeral.

Hordes of workers are putting up metal railings along the funeral route, while TV equipment is being rigged up at St Paul's Cathedral.

Wednesday's ceremonial funeral is expected to see the biggest security operation in London since last year's Olympics.