The twister affected 110,000 people in Daoxian County when it hit the area around 3 a.m., Xinhua reported.
One person died when a house collapsed, while two other people died at hospitals.
More than 2,000 people, including police officers, firefighters and residents, are engaged in relief efforts.
The tornado had a wind speed of 68.7 mph, a local meteorological observatory reported, noting that was a record for the facility.
Electric power has been restored to most of the affected areas.