Rescuers work at a traffic accident site at the Lanzhou south toll station on the Lanzhou-Haikou Expressway in Lanzhou, capital of northwest China's Gansu Province, Nov. 3, 2018. By 5 a.m. Nov. 4 (2100 GMT Nov. 3), 15 people were dead and 44 others injured in the 31-vehicle pile-up in the accident Saturday evening. (Xinhua/Chen Bin)

Rescuers work at a traffic accident site at the Lanzhou south toll station on the Lanzhou-Haikou Expressway in Lanzhou, capital of northwest China's Gansu Province, Nov. 3, 2018. By 5 a.m. Nov. 4 (2100 GMT Nov. 3), 15 people were dead and 44 others injured in the 31-vehicle pile-up in the accident Saturday evening. (Xinhua/Chen Bin)

Rescuers work at a traffic accident site at the Lanzhou south toll station on the Lanzhou-Haikou Expressway in Lanzhou, capital of northwest China's Gansu Province, Nov. 3, 2018. By 5 a.m. Nov. 4 (2100 GMT Nov. 3), 15 people were dead and 44 others injured in the 31-vehicle pile-up in the accident Saturday evening. (Xinhua/Chen Bin)