The Bangladesh government should stop garment factory owners from intimidating and threatening workers for organising trade unions, and prosecute those responsible for attacks on labour leaders, Human Rights Watch said Thursday.
Foreign buyers, including major US and European retailers, should ensure that their Bangladeshi suppliers respect labour rights, it said.
Human Rights Watch interviewed 47 workers in 21 factories in and around Dhaka. The workers claimed that some managers intimidate and mistreat employees involved in setting up unions, including threatening to kill them.
Some union organisers said they were beaten up, and others said they had lost their jobs or had been forced to resign.
Factory owners sometimes used local gangsters to threaten or attack workers outside the workplace, including at their homes, they said.
Bangladesh amended its labour law in July 2013 after widespread criticism following the collapse of the Rana Plaza building which killed more than 1,100 garment workers.
The labour ministry had previously refused to register all but a handful of unions, but the amendments have made it easier for unions to be formed.
More than 50 factory-level unions have been established. But since the law still requires union organisers to get the support of 30 percent of the factory's workers before registering a union, employer threats and intimidation make it a difficult task, especially in factories employing thousands of people.
"The best way to avoid future Rana Plaza-type disasters and end the exploitation of Bangladeshi workers is to encourage the establishment of independent trade unions to monitor and protect workers' rights," said Brad Adams, Asia director at Human Rights Watch.
"The government has belatedly begun to register unions, which is an important first step, but it now needs to ensure that factory owners stop persecuting their leaders and actually allow them to function."
There are more than 5,000 garment factories in Bangladesh. The US and European Union have both linked Bangladesh's continued access to trade preferences to making urgent improvements in labour rights and workplace safety.