"The last thing we want to do is put divers in the water with changing currents, low temperatures, very poor visibility and so much metal and unknown objects in the water. All it takes is for one object to strike an individual, and all of a sudden we have a First Responder trying to recover another First Responder," said Roland L. Butler, Jr., Superintendent of Maryland Department of State Police.

The Singapore-flagged container vessel named Dali, heading out of the harbor bound for Sri Lanka, plowed into a support pylon of the Francis Scott Key Bridge over the mouth of the Patapsco River at about 1:30 a.m. (0530 GMT).

A trestled section of the of the 1.6-mile (2.57 km) span almost immediately crumpled into the icy water, sending vehicles and people into the river.

Rescuers pulled two survivors to safety, one of whom was hospitalized. But active search-and-rescue operations were suspended about 18 hours after the tragedy, authorities said.

The eight individuals were part of a work crew filling potholes on the road surface of the bridge when the accident occurred, officials said earlier.

The ship reported a power failure before impact, which enabled officials to stop traffic on the bridge before the collapse.