The move comes days after Attorney General Eric Holder pledged his department will move “aggressively and appropriately to counter emerging threats” against theft of US intellectual property. The case could heighten US-Chinese tensions over clean-technology trade and domestic subsidies.

Charged in federal court in Madison, Wisconsin, were Sinovel Wind Group, Ltd.; its US subsidiary based in Houston; Su Liying, 36, deputy director of Sinovel’s research and development department; Zhao Haichun, 33, technology manager for Sinovel, and Dejan Karabasevic, 40, a Serbian national and former employee in the automation engineering department of AMSC’s Windtec subsidiary in Klagenfurt, Austria.

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