Just 12 per cent of tickets have been sold for the 2016 Paralympic Games, which start in three weeks.
The poor sales figures were confirmed by spokesperson Mario Andrada at a briefing in Rio on Wednesday, where it was also revealed that travel grants for the National Olympic Committees had not been arranged.
Sparsely populated venues have been a familiar sight at the Rio Games and Andrada conceded the total sold for the Paralympics was "a concern".
The London 2012 Paralympics attracted a record 2.7 million spectators.
This year's event begins on September 7.