London 2012: Why so many empty seats at the Olympics?
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Olympic organisers are investigating why many seats were empty during events at some Games venues on Saturday.
Empty seats were seen at the Aquatic Centre in east London, at Wimbledon and at volleyball games at Earl's Court.
Culture Secretary Jeremy Hunt told the BBC's Jon Sopel it was likely that the unused seats belonged to sponsors.
''We are looking at this very urgently,'' he added.