At least 18 people were injured early Friday when a minivan plowed into pedestrians in downtown Shanghai, according to Chinese state media. Local authorities said three of those hurt suffered serious injuries but gave no further details. Police have said they believe the crash was an accident. The driver was reportedly smoking while transporting several gas tanks, causing a fire inside the vehicle. Eyewitnesses cited in local media reports said the vehicle was on fire before it mounted the pavement and struck several people in front of a Starbucks, according to Reuters.