Tens of thousands of demonstrators marched through the streets of London today in the biggest public protest yet in Britain against the Israeli offensive in Gaza.

The march began in Hyde Park, where Speakers' Corner was turned into a sea of Palestinian flags and banners condemning Israel, before making its way to Kensington Gardens. There were scuffles outside the Israeli embassy as the march passed by the gates leading to its entrance.

Missiles were thrown at police guarding the way and a number of loud bangs – believed to be firecrackers – were heard as riot police drew batons and attempted to push the crowd back from the gates.

A number of younger masked demonstrators attempted to climb on to the gates, near Kensingon High Street, and hurled pieces of placards and other items at police lines.

Panic rippled through the crowd, which included young children, and a number of people fell to the ground amid the scuffles.

A Metropolitan police spokesman said: "A group of protesters outside the embassy of Israel started trying to push over the barriers placed there to protect the embassy. Protesters have also attempted to throw barriers and other missiles at police.

"Officers have been deployed in protective equipment as a precautionary measure after coming under attack from a small minority of protesters."

The march began largely peacefully and included many young British Muslims as well as members of political parties. The crowd listened to speakers including trade unionists, representatives of Palestinian exiles, and celebrity campaigners such as Brian Eno and Annie Lennox.

The Stop The War coalition, which organised today's demonstration, said it believed as many as 100,000 people were taking part in the rallies at Hyde Park and in Kensington Park Gardens.

Richard Elborne, from west London, stamped his feet against the cold and explained why he felt it was important to come with his daughter Louise, five, who had made her own placard calling for an end to the violence in Gaza.

"I've been following what has been happening closely and was always against the Israeli invasion but the bombing of this school really brought it home for me and was an escalation too far," he said.

Eaisha Tareen, a physiologist from Colchester who had travelled with members of her family to take part in the demonstration, said: "It is really unbelievable what is happening in Gaza but we are heartened by the solidarity people here are showing.

"We were coming here on the underground and met a Jewish lady who had written a letter to the newspapers condemning the Israeli action and we were really impressed by that. As you can see here today, it is not just Muslims – there are people from all parts of British life."

As well as the Stop The War Coalition, the British Muslim Initiative and the Palestine Solidarity Campaign were represented in the crowd.

The author Tariq Ali said: "You always have on any demonstration a group of people who get very angry and sometimes that comes out in violence, but for me the most appalling violence is happening in Gaza. A few punch-ups outside the Israeli embassy is neither here nor there."