Spectators at Greenwich Park were today met with banks of empty seats on the first day of six days of Paralympic dressage at the venue, prompting angry outbursts on social media.
Tickets have been unavailable on the website and organisers had said that all sessions were sold out.
As the arena needs resetting and redressing between each grade, days have been split in to two sessions, morning and afternoon, with a lengthy lunch break.
Tickets have been sold separately for the two sessions, so all spectators have to leave the venue before the second session spectators can enter.
Spokesman for LOCOG Anna Greenway explained: “We only released 10,000 tickets as we are limited by the number of people it is possible to get in and out of the venue in a short space of time.”
The situation is being reviewed and if capacity can be increased, more tickets will go on sale.
“But we think our calculations have been pretty robust,” added Anna.