A human rights group wants some major banks to reevaluate their ties to banks in Zimbabwe, saying the ties indirectly support the trade in so-called “blood diamonds.”

Partnership Africa Canada says the banks, including Britain's Barclays and South Africa's Standard Bank, are not involved in the Zimbabwe diamond trade. But the organization says the banks partner with Zimbabwean banks that have ties to the Marange diamond fields.

Human rights activists have accused Zimbabwe's military of killing local miners and running a forced labor operation in the fields.

In a statement sent to VOA Tuesday, Standard Bank refuted the accusation from Partnership Africa Canada. It says the group misunderstands its relationship with the Commercial Bank of Zimbabwe.

Spokesman Ross Windstorm said Standard Bank represents clients who own shares in the Zimbabwe bank, but does not itself own shares.

A Barclays spokeswoman reached by VA declined to comment.

Blood diamonds are gems mined and sold to finance war or violence, usually in Africa.

Reports that Zimbabwe's military had forcibly taken over the Marange diamond fields first surfaced about four years ago. As a result, sales of diamonds from Marange were restricted by the Kimberley Process, the consortium set up to stop the export of blood diamonds.

Zimbabwe has fought the restrictions, and the debate over whether they should be in place continues.

A report released Tuesday by rights group Human Rights Watch says Zimbabwean police, along with guards employed by private mining companies, have been attacking miners suspected of illegally digging in Marange.

The report says the police and guards shoot, beat and use dogs to attack the miners, calling the actions “inhuman, degrading and barbaric.” There was no immediate reaction to the report from Zimbabwean officials.