Evidence of poor safety standards at construction sites for next month's Olympic Games in Athens has been found by a BBC radio programme.
The organisers insist all Olympic facilities will be ready in good time
Many workers have been killed - many more than the official death toll of 14, a Greek union representative said.
But, he told the programme, no official numbers are being kept.
The BBC team observed workers - many from Eastern Europe and South Asia - operating without protective equipment and with minimal supervision.
Speaking on BBC Radio 4's Face the Facts programme, Greek Olympic Committee President Lampis Nikolaou admitted that the death toll in Athens was far greater than in any other city to have recently hosted the games.
One person died in the construction of the Sydney Olympics and two in that of the Barcelona Olympics.
"The human price is very high for me," Mr Nikolaou said.
"This is something that I regret very much but in every country, in every workplace, accidents happen and people die."
The BBC team visited some of the 39 new sites still under construction for the Olympics with British health and safety expert Tom Mellish.
With widespread evidence of poor safety standards, no protective clothing, and little or no apparent organisation, such sites would be closed down in the UK, he said.
"You can see the debris, you can see the disorder... that gives you a clue that these sites aren't organised, they aren't being managed properly and that's a general view.
The Faliro arena is the first Olympic building to be completed
"You get down to some of the detail then you get some real howlers for health and safety."
Mr Mellish said that in his view, the Athens experience raised questions for the International Olympic Committee about which countries were truly suitable to host the games in future.
Tackled by Face the Facts presenter John Waite, the general secretary for the Olympic Games, Spyros Capralos, admitted he had no idea how many workers have died constructing the games.
"We have accidents in the streets, we have accidents everywhere on a daily basis and we don't talk about this.
"But we have taken all the necessary measures (so) that we don't have any accidents in the preparation of these Olympic Games."
"We have managed to do a lot in a very short period of time and I don't know other statistics for other countries... but I think that we have first-class facilities, well-built and I think that overall the result is a good result."
Eventually Mr Capralos became so exasperated by the line of questioning that he called the interview to a halt and walked away.
The general secretary of the Greek Construction Workers' Union, George Theodorou, told the programme he had collected names and details of 14 workers who had died on Olympic facilities.
But he believes there have been many more deaths on all the supporting infrastructure, like Athens' new roads, tram lines and metro, taking the actual death toll to 40.
"Men are being forced to work long shifts, up to 14 hours a day every day, in very hot temperatures and under constant pressure to complete construction work in time for the Olympics," he said.
"Most have no hard hats or safety boots and if they complain, they're sacked. "
Greek opposition MP Liana Kanelli told the BBC that the problems arose because although Greece had seven years to prepare for the games, more than half of that time was taken up by legal battles.
"There wasn't a brick laid for the first three-and-a-half years. We've now got about one injury or one death every couple of days.
"This is a Greek tragedy that we will have to face after the Olympics."