Workers involved in the restoration of the areas hit by the March 11 earthquake and tsunami and the troubled Fukushima Daiichi nuclear plant say their working conditions have been harsh.
About 1,500 temporary workers of subcontractors hired by leading construction companies gathered in Tokyo on Sunday to discuss the situation.
A man who took part in the construction of emergency housing in Iwate Prefecture said he had been promised 20,000 yen, or 250 dollars, per day, but received only about one-third of the amount.
The workers were forced to work without any explanation about the risk of radiation or any measures against heat strokes.
The organizers say these issues have not surfaced before because many workers find it inappropriate to complain when
they think about the hardships of people in the disaster-hit areas.