The SUV involved in the incident was driven by Usmen Hasan, a man whose name suggests he is an ethnic Uighur - Muslims from the far western region of Xinjiang, police said.
His wife and mother were also with him in the car, along with devices filled with gasoline, knives and a flag with "religious extremist content" written on it, police said.
The five people connected with the incident were arrested with help from the Xinjiang government. Police also seized jihadist flags and knives from where they were staying.
Two tourists were also killed in Monday's incident and at least 38 people injured.
Xinjiang is home to the Turkic-speaking Uighurs, many of whom chafe at China's controls on their religion and culture and there have been violent clashes there in the past.
Rights groups say China exaggerates the threat to justify its harsh rule.