All recording devices are prohibited at the dress rehearsals for the August 8 opening of the Beijing Olympics in the wake of footage from a previous test run being leaked onto the internet, reported dpa.
The organizing committee BOCOG said on Saturday that cameras, video cameras and recording equipment on mobile phones are prohibited for the two rehearsals, later in the day and on Tuesday.
BOCOG said that "any information leaked to the public about the opening ceremony will be dealt with severely."
South Korean television SBS reportedly recorded part of an earlier rehearsal and some of it was posted on the popular YouTube website.
But it was swiftly removed after the International Olympic Committee and BOCOG intervened.
Opening ceremonies are always a big Olympic secret and there are expectations that Friday's event in Beijing will be a spectacular one, with costs estimated at 300 million dollars.