An investigation is under way into allegations that Olympic officials and agents were caught offering thousands of top tickets to the London Games on the black market.
The International Olympic Committee (IOC) called an emergency meeting of its executive board after The Sunday Times newspaper presented a dossier of evidence on officials controlling the tickets for 54 countries.
Thousands of the best seats at the top events - including the 100m final - were up for sale after being siphoned off from official supplies held by overseas national Olympic committees (NOCs), the newspaper said.
The allegations are now to be investigated by the IOC's ethics commission, a senior IOC source has confirmed to the Press Association.
The IOC will also consider a complete shake-up of how Olympic tickets are distributed among member countries.
The NOCs are forbidden to sell their tickets abroad or to anyone who plans to resell them.
But The Sunday Times said undercover reporters posing as envoys of a Middle Eastern ticket tout found 27 officials and agents who were willing to do business.
According to the paper, these included one country's official ticket agency which The Sunday Times claimed offered category AA tickets, the best seats in the stadiums, to the fake Middle Eastern tout for up to £6,000 each.
The latest allegations come after one of Ukraine's leading Olympic figures resigned when he was filmed offering London 2012 tickets for sale on the black market.
Volodymyr Gerashchenko, the 66-year-old general secretary of the Ukraine National Olympic Committee, quit last month but said he will co-operate with the independent investigation commission that was launched last week.