Earlier reports indicated that at least 50 people were injured and four others were killed as a result of the blast.
According to China Central Television, the incident occurred on a freeway in the Tai Zhou district of the province at 16.40 local time (08:40 GMT). It is not yet known what caused the truck to explode.
Nearby residential buildings were lightly damaged following the blast. Firefighters, rescuers, doctors and law enforcement officers have already arrived at the scene.
Videos of the explosion have been shared online.