Police and FBI officials have descended on an apartment building in Stamford, Connecticut where the driver lived.
Teams wearing hazardous materials suits appeared to be preparing to enter the building and bomb squad truck was seen driving to the area.
Residents said they had been evacuated shortly after 5pm local time (10pm UK time).
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The tranquil district of Hart has been crowned as the place with the best quality of life in the UK for the fourth year in a row.
Britain's immigration system is in 'critical condition' according to the chair of the Home Affairs Select Committee.
Showers across Britain will make way for sunshine tomorrow before a milder end to the weekend, though heavy rain will return in the north.