A Baltimore bridge has crashed into the Patapsco River after being struck by a large boat this morning.

Footage from Maryland showed the 9,000-foot structure crumbling after the vessel collided with one of its pillars.

Baltimore Mayor Brandon Scott revealed emergency services were on scene following the incident.

Baltimore City Fire's PIO later confirmed at least seven people were believed to be in the Patapsco River.

Chief Kevin Cartwright said "as many as seven individuals and several vehicles" have fallen into the river.

The structure is estimated to carry around 12 million vehicles every year.