Rohingya refugees attempting to reach Malaysia by boat from Bangladesh are being held hostage by human traffickers who have demanded large ransoms from their relatives with threats of violence, according to several families and aid organizations.

About a dozen Rohingya refugees living in camps in Bangladesh said they had received phone calls from traffickers demanding money to stop relatives from being abandoned at sea and, in some cases, raped or killed.

More than a million mostly Muslim Rohingya reside in camps in Bangladesh, with the majority having fled a 2017 army-led crackdown in largely Buddhist Myanmar.