The International Olympic Committee insists it has 'complete confidence' over safety at next year's London Olympics.
An IOC spokesman says security is a top priority but that it's not its direct responsibility.
The British Olympic Association director of communications Darryl Seibel says he's confident that the Games will pass off safely.
London test events in beach volleyball, badminton and cycling will go ahead this week.
The rioting exploded as two senior members of the IOC co-ordination commission, Denis Oswald and Gilbert Felli arrived for a project overview.
And a further 200 representatives of National Olympic Committees will be in London, attending seminars, about Games-time arrangements.
