Image copyright EPA Image caption The procession was led by children, police and faith leaders

Yellow roses and banners saying "Islam says no to terror" and "please don't kill innocent people" were in the hands of schoolchildren aged nine and 10.

They were leading a procession on a packed Westminster Bridge to mark a week since Khalid Masood killed four people and injured 50 in an 82-second attack.

Standing with them were senior police officers and faith leaders, many carrying banners themselves with the words "love for all, hatred for none".

Quietly but surely the group processed towards the scene of the attack, passing some of the nurses and doctors from St Thomas' hospital who treated victims at the time.

Then quiet fell as a silence was held at 14:40 BST - the exact moment a week ago that Khalid Masood began his attack.

There was almost silence, apart from the noises of police helicopters overhead - a reminder of the vigilance needed to police such an event and the ongoing threat police have to guard against.

After a few minutes the crowds gathered on either side of the road were pushed back to allow people to lay flowers near the scene of the attack.

Police officers, medical workers, schoolchildren and religious leaders were among those who laid single roses and daffodils.

A male victim of the attack, who appeared to have a broken leg, was pushed in a wheelchair to lay a flower on the bridge.

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Unsurprisingly for a tourist destination like Westminster, where so many come just to spend a few hours of sightseeing, many of those who had gathered to watch the service had not known beforehand it would be happening.

But the sight of large crowds of police - some armed with machine guns, others on horseback - suggested this was no ordinary day in Westminster.

As the crowds began to get bigger, passersby would stop to ask "what's happening?", or take photographs, before invariably staying to watch.

Others, many from London's Muslim community, came to the event prepared with banners and placards with messages of peace and solidarity.

Hundreds of members of the Ahmadiyya Muslim Youth Association were among them.

Many wore T-shirts with the message "I am a Muslim, ask me anything", while others carried whiteboards asking people what message they would like to send to Muslims.

Periodically, people would stop to talk to them or shake their hands in recognition.

Zafir Malik, an imam from the association, said they were asked by the police to come along to show solidarity.

He said they wanted to "show that what happened here last week had nothing to do with the so-called religious aspect that this has been given".

Image caption L-R: Zishan Ahmad, with his brother Danyal, said "You can't divide London"

Image caption Brendan O'Connor said the service showed those who sought to divide London were "not going to stop us"

Zishan Ahmad, a 25-year-old Imam, who is also part of the group, added: "You can't divide London - we stand together.

"It doesn't matter if you are Muslim, Christian or Jew, or black, brown or any other race. London will never be divided.

"This is the most multicultural city in the world. I've lived in Holland and Germany but I've never seen anything like London."

Brendan O'Connor, from Holborn, central London, said the memorial service sent a message that those who would seek to divide London are "not going to stop us".

The 59-year-old added: "There's love here. You can't kill love with hate. Love always conquers."