Discussions about a multibillion dollar hybrid car plant in Mississippi have been revealed in a federal lawsuit in which Chinese businessmen are fighting for control of the company.

The lawsuit was filed in U.S. District Court in Oxford and unsealed this week.

U.S. District Judge Michael P. Mills says the lawsuit is an “extraordinarily complex case involving a $6.5 billion project, proposed to be financed by Chinese investors, to build a hybrid car factory in Tunica, Mississippi.”

State officials wouldn’t comment and it’s not clear how far along negotiations are.

Mills said the parties involved in the case have worked with Mississippi Gov. Haley Barbour, the Mississippi Development Authority and Tunica County “to lay the groundwork for the project.”