The timing could not have been worse. This week, executives from the International Olympic Committee and officials from nearly 200 national Olympic committees arrived in London for meetings about the Summer Games. At the same time, several test events, including beach volleyball, badminton and cycling, are being held.

“There’s no doubt that this is a very bad day, a worrying day, for Olympic organizers in London,” said Tony Travers, a professor at the London School of Economics who has studied the impact of the Olympics on the city. “They planned to protect London from conventional terrorism. But of all the things they might have thought might happen, I’d be surprised if civil insurrections was high up on their list of expected risk factors.”…

The top American beach volleyball players April Ross and Jen Kessy competed in the event, later saying in a telephone interview that they felt safe at the site because of the increased security. Ross said there were X-ray machines and full body scanners at the entrance to the site, as well as a visible police presence.

“If we didn’t see the riots on the news, we wouldn’t have any idea that they were going on,” she said, adding that she and Kessy have been glued to the television since arriving on Sunday.