Seventeen people were arrested on Saturday as thousands of pro-Palestinian protesters marched through central London. The march was organised by groups including the Palestine Solidarity Campaign and the Stop The War Coalition.
Some protesters carried signs declaring support for Hezbollah. The Met Police said it was searching for the people involved after posts appeared on social media.
A counter-protest supporting Israel also took place, with police forming a cordon between the two marches. But a small group broke away from the pro-Palestinian protest and were stopped trying to approach the counter-protest at Aldwych. Three people were arrested after officers intervened.
The counter-protest group was moved back to Trafalgar Square as it got "too close to the main march and well away from the agreed area", according to police.
Police said three people had been arrested for assaulting an emergency worker, three for assault, eight for public order offences (four racially aggravated), one for a breach of Public Order Act conditions and two for supporting a proscribed organisation.
One of those arrested for supporting a proscribed organisation was seen wearing what appeared to be a parachute.