LANZHOU, Oct. 23 -- A train accident left three people dead and one seriously injured on Wednesday night in northwest China's Gansu Province, local authorities said on Thursday.

A freight train numbered "10152" hit and ran over a group of people who violated crossing rules at the tracks between Liang Jiaping Station and Dingxi Station at around 9:48 p.m. on Wednesday, according to the local work safety department.

The train belongs to the railway bureau of Lanzhou, the provincial capital city, it said.

"The accident happened in the field. We don't know how the pedestrians got to the track right now," said an investigator who declined to be named.

Further investigation is underway.