A leading international rights group says suspects accused of involvement in Bangladesh's 2009 border guard mutiny are being subjected to widespread abuse, torture and deaths in custody.

The 2009 revolt resulted in the deaths of 74 people, including 57 army officers. The mutineers said they were protesting low pay and other grievances.

More than 4,000 border guards are accused of crimes associated with the mutiny, including murder, looting and arson. Several hundred have been sentenced by a special court.

In a report released Wednesday, Human Rights Watch urges Bangladeshi authorities to halt mass trials and establish an independent task force to investigate and prosecute alleged human-rights abuses after the mutiny.

The New York-based group says at least 47 suspects have died in custody. Detainees have been subjected to beatings, electric shock and other torture.

Human Rights Watch Asia Director Brad Adams says, “those responsible for the horrific violence that left 74 dead should be brought to justice, but not with torture and unfair trials.”

The group says torture is routinely used by Bangladesh security forces, even though the country is a state party to the United Nations Convention Against Torture.

Human Rights Watch also repeated its concerns about the “enormous number of people convicted after mass trials before specially created military tribunals and civilian courts.” Many of the accused have not had adequate counsel, “adequate time to prepare a defense or access to the evidence against them.”

Bangladeshi officials contacted by news agencies rejected the allegations of rights abuses — saying suspects have been treated fairly and not tortured.