DETROIT -- A former General Motors engineer with access to the automaker's hybrid technology was convicted Friday along with her husband of stealing trade secrets for possible use in China.

Shanshan Du won a transfer within GM in 2003 to be closer to the technology and then copied documents until she accepted a severance offer and left the company in 2005, prosecutors said. Prosecutors said the technology was worth at least $40 million, the price that other automakers paid GM to get it.

Du and Yu Qin were found guilty Friday by a federal jury in Detroit after a trial that lasted weeks. Qin also was convicted of wire fraud and attempting to obstruct justice by shredding documents. They shook each other's hand after the verdict but declined to comment, as did their attorneys.

The couple face up to 20 years in prison. No sentencing date has been set.

Prosecutors told jurors that GM trade secrets were found on at least seven computers owned by the Oakland County couple. The government doesn't believe the information ever made it to China, although Qin had set up his own company, Millennium Technology International, and claimed to have made contact with GM competitors overseas.