A Detroit couple was charged on Thursday in a U.S. court with conspiring to steal trade secrets related to hybrid vehicles from General Motors to pass on to Chery, a major Chinese car marker.

"We had no idea about this issue until we read about in the media," Jin Yibo, spokesman for Chery, told Reuters by telephone.

"It seems strange to us and we don't understand why Chery's name is being linked to this matter."

Yu Qin, 49, and his wife Shanshan Du, 51, of Troy, Michigan, were charged in a seven-count indictment that was unsealed on Thursday in U.S. District Court in Detroit.

Qin and Du, who worked as a GM engineer, are accused of trying to pass stolen information to Chinese automakers through a small firm they owned called Millenium Technology International.

Du is accused of copying thousands of GM documents to an external hard drive five days after the automaker offered her a severance agreement in January 2005.

She left GM's advanced technology group in March 2005. In August, Qin and Du proposed a joint venture on hybrids to China's Chery in a series of emails, according to the indictment.

Then in November 2005 Qin applied for jobs as a hybrid engineer, claiming on his resume that he had invented some of the stolen GM technology, prosecutors say.