The Mayor's Office has confirmed Boris Johnson authorised the highly-controversial purchase of water cannon - despite not yet getting the go-ahead from the Home Secretary.
City Hall says buying the German vehicles now will mean savings of £2.3million compared to buying new water cannon and ensures they are ready as soon as possible'.
More top news
Reclaim the Power stage a protest at Heathrow against a new runway or further airport expansion.
Eight more people were hurt in the collision.
Police are hunting a man who is suspected of grabbing an 11-year-old girl who only got away by biting her attacker's hand.