Another 151 participants were confirmed safe, of which eight with minor injuries were treated in the hospital.
It was a public safety incident caused by a sudden change in local weather, and the province had set up a special team to further investigate the cause of the incident, said Zhang Xuchen, mayor of Baiyin city, yesterday morning.
The marathon race was held on Saturday morning in the Yellow River Stone Forest tourist site in Jingtai county, Baiyin city.
According to the rescue headquarters, at about 1pm on Saturday, hails, freezing rain and gales hit the area.
Participants suffered from physical discomfort and loss of temperature due to the sudden drop in air temperature.