Twenty-two foreign trainees died in work-related incidents in the three years from fiscal 2014, government data showed Sunday, indicating people brought to Japan to work may face dangerous or exploitative conditions.

While most of the 22 deaths are believed to be accidents, one resulted from overwork, the Ministry of Health, Labor and Welfare data showed. The figures are the first government statistics released on work-related deaths among foreign trainees.

Over the three years, there were on average 475 cases of work-related accidents involving foreign trainees that were subject to compensation from industrial accident insurance and required four or more days of leave, the data showed.

Japan introduced the training program for foreign workers in 1993 with the apparent aim of transferring skills to developing countries. But the scheme, applicable to agriculture and manufacturing among other sectors, has drawn criticism at home and abroad for giving Japanese companies cover to import cheap labor.

Cases of illegally long working hours, unpaid wages, violence and other harsh conditions have also been reported.

According to the Justice Ministry, the number of foreign trainees is on the rise, with 167,641 registered in 2014, 192,655 in 2015 and 228,589 in 2016. With 22 deaths over the three year period, the ratio of work-related deaths is roughly 3.7 deaths per 100,000 trainees.

As a nation as a whole, meanwhile, labor ministry data shows that work-related deaths in all industries totaled 2,957, or 1.7 per 100,000 workers.