Female workers in Cambodia have suffered mass faintings due to excessive hours worked in stifling conditions in factories that supply garments and accessories to sportswear brands including Nike, Puma, VF Corporation, and Asics. According to reports from The Observer and Danish investigative media site, Danwatch, more than 500 laborers in four factories have been hospitalized over the past year due to sweatshop conditions.

The Observer/Danwatch investigation found that female factory workers are being subjected to shifts lasting upwards of 10 hour per day, six days a week and in factories that reach over 100 degrees Fahrenheit. In one three-day period in November 2016, 360 workers collapsed on the job.

As reported by the Guardian, “Workers feared for their lives in one incident when 28 people collapsed rushing to escape a fire at a factory supplying Nike. Another described panic after thick smoke seeped into a factory supplying Puma.”

Puma, Nike, VF Corporation and Asics, which were contacted by the Observer, claim to have investigated all of the episodes at issue, some of which took place as recently as this past March. A spokesman for Nike specifically said that company installed air conditioning and cooling systems in its factories.

Kering-owned Puma “said it made recommendations, including providing energy bars and medical checks, maintenance of the ventilation system and a worker management committee. Puma is now replacing short-term contracts for workers who have given more than two years’ service. It was engaging with Better Factories Cambodia – a partnership between the United Nations’ labor organization and the International Finance Corporation.”

The VF Corporation – which owns Wrangler, North Face, Nautica, and Vans, among other brands – said is working to legal proper working conditions are observed “in [their] contract supplier factories, including temperature or working breaks.”

The report coincides with news that at least 16 home-bound apparel workers, including a 10-year old girl, were killed and nine others injured when a truck carrying them overturned in Rangpu, Bangladesh on Saturday.

According to local news sites, “The working class victims, who had been living in Gazipur, had been travelling on the truck to go to their village homes at a cheaper fare as transport operators hiked the fare cashing in on the huge demand of tickets ahead of [Eid-al-Fitre, one of the two major festivals of Muslim world], survivors said.”