Thousands of extra police officers will be deployed in central London and elsewhere . There had been speculation the carnival , which its organizers say is Europe 's biggest street festival , might be canceled after the disorder that hit the capital 's streets three weeks ago . More than a million people are expected to attend the three - day Notting Hill Festival . Police say intelligence indicates some gangs are planning to start riots . Three weeks ago , London was hit by outbreaks of rioting and looting .
Thousands of extra police officers will be deployed in central London and elsewhere . More than a million people are expected to attend the three - day Notting Hill Festival . Police say intelligence indicates some gangs are planning to start riots . Three weeks ago , London was hit by outbreaks of rioting and looting .