A major bridge in Baltimore, Maryland, partially collapsed Tuesday morning, possibly leaving a number of people in the river below, police said.

A spokesperson for Baltimore Police Department told NBC News that it had been notified of the incident at the Francis Scott Key Bridge, an enormous steel structure which carries the Interstate 695 over the Patapsco River southeast of the Baltimore metropolitan area.

“I can confirm at 1:35 a.m., Baltimore City police were notified of a partial bridge collapse, with workers possibly in the water, at the Francis Scott Key Bridge,” Detective Niki Fennoy said in a statement.

Baltimore County Executive Johnny Olszewski, Jr. said on X that he was aware of the incident and in touch with the fire service chief, the mayor of Baltimore and other local officials. "Please pray for those impacted," he said.

NBC News has contacted the U.S. Coast Guard and other emergency response agencies for further details.

The Maryland Transport Authority confirmed that the I-695 was shut because of the Key Bridge collapsing due to a "ship strike."

Built in 1977 and referred to locally as the Key Bridge it later named after the author of the American national anthem. The bridge is more than 8,500 feet, or 1.2 miles, long in total. Its main section spans 1,200 feet and was one of the longest continuous truss bridges in the world upon its completion, according to the National Steel Bridge Alliance.