The National Development and Reform Commission (NDRC) asked local officials to investigate construction and production details of projects related to Evergrande New Energy Vehicle and Baoneng that started from 2017, according to the document dated Nov. 13. Two people familiar with the matter confirmed its authenticity.
An official at NDRC told Reuters they are "checking the document" but declined to comment further.
Evergrande and Baoneng, a property and financial services conglomerate, could not immediately be reached for comment.
Evergrande New Energy Vehicle's shares in Hong Kong fell 7% on Wednesday, compared with a small gain for the broader benchmark index.
China published rules in 2018 to restrict ways in which automakers can invest in new capacity to manufacture traditional gasoline-fueled cars as well as electric battery cars.
NEVs include battery-powered electric, plug-in petrol-electric hybrid and hydrogen fuel-cell vehicles. China expects sales of NEVs could reach 1.1 million vehicles this year.
(Reporting by Xu Jing, Yilei Sun and Tony Munroe; Editing by Himani Sarkar and Kim Coghill)