More evidence has emerged that the security forces in Zimbabwe are operating torture camps in the Marange diamond fields.
Former prisoners have told the Panorama programme on BBC they had been severely beaten several times a day and women in the camps were routinely raped.
Two witnesses say dogs had been used to maul prisoners.
The people held in the camps are accused of illegally digging for diamonds.
The government of Zimbabwe has not responded to the accusations.
The European Union is pushing to let some banned diamonds from Zimbabwe back onto world markets.
In an internal document seen by the BBC, the EU said it was confident that two mines in the area now meet international standards.
It wants diamonds from those areas to be immediately approved for export, which would partially lift a trade ban dating back to 2009.
The ban was imposed by the Kimberley Process, an international organisation that polices diamonds, following reports of large-scale killings and abuse by Zimbabwe's security forces in the Marange diamond fields.
The BBC reports the company that runs the main Mbada mine that the EU wants to approve exports from, is headed by a personal friend of President Robert Mugabe.