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Chinese firms pose spy threat, says US panel

8 October 2012 Last updated at 17:39 BST

Chinese telecom firms Huawei and ZTE pose a security threat to the US, a congressional panel has warned after an investigation into the two companies.

The panel says the firms failed to allay fears about their association with China's government and military.

The firms - among the world's biggest makers of networking equipment - denied the accusations in front of the panel.

John Sudworth reports.