Under St Paul's Cathedral's famous dome, Margaret Thatcher, former British prime minister, was laid to rest on Wednesday.

As one of few journalists that can cover the funeral in St Paul's, I arrived there as required by 9 am.

Under a light drizzle, hundreds of spectators stood outside the cathedral, some of whom had camped out overnight to witness the event.

More than 4,000 officers were on duty for Lady Thatcher's funeral to guard against violent demonstrations.

"The road along the route from Whitehall to St Paul's Cathedral was closed," a policeman who stood outside the cathedral said.

Shops that line the route of the procession were asked to hide anything that could be used as a weapon by protesters.

Union flags and national flags of the UK were lowered to half-staff above Downing Street and at landmark buildings, and were to remain so until dusk.

The queen and Duke of Edinburgh arrived at the Cathedral at 10:45 am. It was the first time the monarch attended a funeral for a British prime minister since that of Winston Churchill in 1965.

As Lady Thatcher's coffin traveled along the procession route to the cathedral, Big Ben fell silent and the cortege drove slowly through the cordoned-off streets in central London, past Westminster Abbey and into Parliament Square.

A single cannon was fired in salute from Tower Wharf for each minute of the procession as the muffled bell of St Paul's tolled.

The most moving part of the service occurred when the coffin of Lady Thatcher — draped in a union flag, with a simple wreath of white flowers atop — was brought into the cathedral.

"It was then, when you looked around the congregation, the most tears appeared in people's eyes," one broadcaster said.

However, my friend who stood along the Strand told me: "A handful of protesters turned their backs as the coffin went past. Angry exchanges broke out between supporters and demonstrators as the gun carriage made its way."

The Bishop of London sidestepped the political controversy surrounding Lady Thatcher in his address. The funeral concluded after about an hour.

When I walked outside the cathedral, it was sunny. I thought of the address of the Bishop of London: "After the storm of a life led in the heat of political controversy, there is a great calm."