There are grave fears for at least seven people after a bridge collapsed when it was struck by a large ship.
Footage captured the moment the ship collided with the Francis Scott Key Bridge in Baltimore about 1.30am Tuesday, local time.
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Mayor Brandon M Scott and Baltimore County Executive Johnny Olszewski Jr said emergency personnel are responding and rescue efforts are underway.
According to the Associated Press, at least seven people are in need of assistance.
Emergency responders are searching for at least seven people believed to be in the water, director of communications for the Baltimore Fire Department Kevin Cartwright told the Associated Press about 3am local time.
Multiple vehicles were on the bridge at the time of the crash, including one the size of a tractor-trailer, Cartwright said.
“Our focus right now is trying to rescue and recover these people,” he said.
It is too early to know how many people were affected by the incident, but the collapse is a “developing mass casualty event”, Cartwright said.
It appears there are “some cargo or retainers hanging from the bridge,” creating unsafe and unstable conditions, and that emergency responders are operating cautiously as a result, he said.
“This is a dire emergency,” Cartwright said.
All traffic is being detoured due to an “incident”, the Maryland Transportation Authority (MTA) said on social media.
The ship is believed to be a Singaporean container ship named Dali.
Dali can be seen stopped underneath the Francis Scott Key Bridge on maritime data platform Marine Traffic.
The ship is 299.92m long and 48.2m wide and was leaving Baltimore for Sri Lanka.
The Francis Scott Key bridge was originally known as the Outer Harbor Crossing and extends over the Patapsco River.
It is a 1.6-mile (2.5km), four-lane bridge.
It serves as the outermost crossing of the Baltimore harbour and an essential link of Interstate-695, or the Baltimore Beltway.
Its namesake, Francis Scott Key, is believed to have sat near the site of the bridge as he witnessed the bombardment of Fort McHenry in 1814, inspiring him to write a poem entitled “Defence of Fort M’Henry” which would go on to form the lyrics of the US national anthem “The Star-Spangled Banner”.
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