Special measures are being taken to protect Notting Hill Carnival from the threat of terrorism and acid attacks, Scotland Yard has said.
Steel barriers and a ban on vehicles during the daytime will be in place over the bank holiday weekend to stop a terror attack.
David Musker, the commander in charge of policing the west London event, said there was no specific counter-terrorism intelligence but security plans had been "thoroughly reviewed" after the Barcelona attack, in which 15 people died after being hit by a van.
Officers will be stationed around the perimeter of the carnival zone, carrying out checks for weapons and acid, following a controversial three-week crackdown to reduce criminality at the event.
There will also be a protective ring of officers around Grenfell Tower and the Lancaster West estate to protect the space from carnival-goers and ensure a "respectful" two days.
A three-week crackdown on crime ahead of the carnival saw 656 people arrested by 7am on Friday, and a large number of knives, guns, weapons and money seized, the Metropolitan Police said.
Last year more than 450 people were arrested over the two days of festivities, with around 300 detained in the preceding crackdown.
The force hit back after being widely ridiculed for linking this year's operation to the carnival, with Mr Musker saying: "I think the public would expect us to do what we can to prevent those injuries to people coming to carnival."
He added that the point had been "to get people who would normally come to carnival to cause problems off the street before the event".