Spectators who attended a preview of the Olympic Games opening ceremony have been urged to keep the details secret and not spoil the surprise for others.
Thousands of people who attended a rehearsal on Monday were asked not to circulate images or videos.
Danny Boyle, the ceremony's artistic director, reportedly addressed the audience to "save the surprise".
About 62,000 are set to attend the opening ceremony at the Olympic Stadium in Stratford, east London, on Friday.
The event is expected to be watched by an audience of billions worldwide.
Olympic organisers Locog said the technical rehearsal for the opening ceremony "went very well".
"The reaction from the attendees has been overwhelmingly positive on social media and crucially they are still helping us to save the surprise for the rest of the nation on Friday," it said.
People who attended the rehearsal reported that the hashtag "#savethesurprise" was emblazoned on giant screens inside the Olympic Stadium.
It later trended globally on micro-blogging website Twitter.
In other developments:
Most people who attended the rehearsal appeared to obey the appeal for secrecy, although there have been reports of some images being posted on the internet before being removed shortly after.
Many took to Twitter to show their support after the rehearsal.
"I am now sitting on my seat in the Olympic Stadium. But I shall #savethesurprise and not tweet details of the ceremony. Sorry," tweeted Dan McNeil.
And many gave positive reviews of the ceremony on the website.
One person who was in the audience, Pete Hendrick, tweeted: "If you've got plans Friday night, cancel them. Opening ceremony is out of this world. Danny Boyle, I salute you."
Chris Golds, another audience member, said the event was "breathtaking" and "awe inspiring".