DETROIT — A Troy, Mich., couple were arraigned in federal court Thursday on charges of conspiring to sell GM's hybrid vehicle secrets to a Chinese car company.

DETROIT — A Troy, Mich., couple were arraigned in federal court Thursday on charges of conspiring to sell GM's hybrid vehicle secrets to a Chinese car company.

Yu Qin, 49, and his wife, Shanshan Du, 51, stood mute in U.S. District Court to a 6-count indictment charging them with unauthorized possession of trade secrets, wire fraud and obstruction of justice.

U.S. Magistrate Mark Randon entered not-guilty pleas on their behalf and released them on $10,000 unsecured bonds, which is common in white-collar criminal cases. The U.S. Attorney's Office said Du, while working for GM, passed hybrid secrets to her husband for use in their company, Millennium Technology International Inc.

About five days after GM offered Du a buyout in January 2005, authorities said, she copied thousands of pages of GM documents to a Millennium Technology external computer hard drive.

A few months later, Qin moved forward with a new venture to provide hybrid technology to Chery Automobile, a GM competitor based in China, prosecutors alleged.

In May 2006, the couple drove to a Dumpster behind a grocery store, where Qin got rid of plastic bags containing shredded documents that had been subpoenaed by a federal grand jury, prosecutors said.

Prosecutors said the stolen documents, which never fell into Chinese hands, were worth more than $40 million.

The couple are Chinese immigrants and naturalized U.S. citizens, authorities said. Their lawyers wouldn't comment on the substance of the charges.