Beijing police are seeking information about eight suspects and five number plates of cars in connection with yesterday's incident that also injured 38 people, the Hong Kong-based South China Morning Post reported.
Earlier, police named two suspects for the crash right in front of the life size picture of Mao Zedong - founder of communist China - at entrance of the iconic Forbidden City overlooking Tiananmen Square.
The police notice said a "major case had taken place on Monday" and named two residents of Pishan county and Shanshan county of Xinjiang Uyghur Autonomous Region as likely suspects.
The SUV's number plates started with regional characters and this showed it was from Xinjiang, according to the notice.
Some reports said three persons inside the car, who were killed when it caught fire, were on a suicide mission.
Xinjiang, home for Uyghur Muslims, has been restive for the past few years as native Uyghurs are protesting against growing settlements of Han Chinese in the province.
If confirmed, this will be the first major incident involving Xinjiang militants in well-guarded Beijing.
