Work is underway to rebuild Baltimore Key Bridge, which collapsed after being hit by a cargo ship last week.

The White House has poured millions of into fixing the port, which brings in billions of dollars of revenue annually.

US Correspondent Richard Arnold says authorities have a long process ahead.

"They have only recovered the remains of two of the six bridge workers who were killed when it all collapsed- the cargo ship and the crew were stuck in the tangle, just sitting on board there."

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