Three police officers were injured and 40 people have been arrested during a protest in Westminster on Tuesday night.
One officer was left with a serious facial injury after she was hit by a bottle thrown from the crowd, while two officers had minor injuries.
Metropolitan Police said the suspect who threw the bottle has not been identified but police are investigating.
A protest organised by a coalition of groups, including the Palestine Solidarity Group, began at around 6pm and was required to end at 8pm, police said.