At least six were killed in the United States' Fort Worth, around 50 kilometres from Dallas, Texas, after nearly 100 vehicles - ranging from small cars, SUVs to 18-wheel trucks - crashed into each other, forming a massive pile up of mangled steel. The local fire department informed that several people were trapped in the pile up. Visuals show dozens of crashed vehicles, badly damaged, strewn around on the road. Local publication Fort Worth Star reported that at least 30 people were taken to hospital. Many of the injured are critical. At least 24 fire units responded to the pile up, it added.