The difficult job of extracting tons of broken concrete, metal bridge beams and submerged cars from the Mississippi River was moving forward in the US today, six days after a Minneapolis bridge suddenly collapsed.

A rush-hour crawl that gave vehicles little momentum to slide into the river and a bridge design that minimised falling debris appear to have kept the death toll relatively low in the collapse of a bridge into the Mississippi River.

Families waited anxiously for news of missing relatives as divers searched through the dangerous debris left by Wednesday’s bridge collapse.