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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Widespread frost for most areas as temperatures dip below freezing.
Premier League clubs have agreed to pay all full-time staff the living wageof £9.15 an hour in London or £7.85 an hour outside the capital.
Tamworth represents what's going on at the national level, a remarkable boom in jobs but wages only just beginning to overtake inflation.