A human rights group says garment factory owners in Bangladesh have been intimidating and threatening workers who try to organize trade unions.

New York-based Human Rights Watch said Thursday that it had interviewed dozens of workers who said they were beaten, lost their jobs or forced to resign after trying to organize unions.

The working conditions in Bangladesh garment factories are often harsh and unsafe. There have been a series of disasters highlighting the poor conditions, including a 2012 fire and a factory collapse last April that killed more than 1,100 workers.

The industry employs 4 million Bangladeshis and Bangladesh earns more than $20 billion a year from exports of garment products, mainly to major retailers in the United States and Europe.