What We Know About the Francis Scott Key Bridge Collapse in Baltimore

Follow our live coverage of the Francis Scott Key Bridge collapse in Baltimore.

The giant container ship that struck and downed the Francis Scott Key Bridge in Baltimore this week remained pinned under the twisted remains of the bridge on Thursday, as officials outlined more plans in their effort to recover the bodies of victims, free the vessel, dismantle the wreckage and reopen the city’s port as quickly as possible.

As part of the cleanup plan, officials were bringing in the largest crane on the Eastern Seaboard, a 1,000-ton piece of equipment that will help pull pieces of the bridge out of the Patapsco River.

On another front, federal investigators said that they were interviewing key crew members and examining hours of data recordings. But the investigation into the ship crash could take years, they said.

The bridge is a part of Interstate 695 and a critical transportation link on the East Coast to one of the largest ports in the country. The disaster has become America’s deadliest bridge collapse in more than a decade.

Six construction workers are presumed dead, including two whose bodies were recovered from the river on Wednesday. The four others were very likely encased in fallen steel and concrete, the authorities said.

Governor Wes Moore and the F.B.I. said there was no credible evidence of a terrorist attack.

Here’s what we know.

Why did the ship hit the bridge?

It’s not yet clear, and investigators from the National Transportation Safety Board boarded the ship on Tuesday night to gather documentation. They obtained data from the voyage data recorder, which is essentially the black box. That has been sent to a lab to help the authorities develop a timeline of events that led up to the crash.

The 985-foot-long cargo vessel, called the Dali, was leaving the Port of Baltimore when it had a “complete blackout” that knocked out power to the engine and the navigation equipment, an industry official said. The ship issued a mayday call just before hitting a critical component of the bridge, known as a pylon or pier. Radio traffic from emergency workers suggested that the crew was struggling to steer the ship, according to audio published by Broadcastify. It was traveling at about nine miles per hour, officials said, which is typical in that zone.

Audio from a Maryland Transportation Authority police channel showed that the mayday call had allowed officers a few precious minutes to close the bridge to traffic. The effort to rapidly shut down traffic probably prevented more cars from being on the bridge during the collapse and saved lives, officials said.

Baltimore harbor pilots were directing the ship at the time of the crash, as is customary when vessels enter ports or canals, according to a joint statement from the ship’s owner and manager. Two tugboats helped the ship steer out of the terminal but then returned to the port for their next ship assignment, port officials said.

Governor Moore said that the bridge was fully up to code and that the collapse did not appear to be the result of a structural issue.

What do we know about the victims?

The two victims recovered on Wednesday were identified as Alejandro Hernandez Fuentes, 35, of Baltimore, and Dorlian Ronial Castillo Cabrera, 26, of Dundalk, Md. Mr. Fuentes was from Mexico, and Mr. Cabrera from Guatemala.

Jose López, a father of two who had emigrated from Guatemala nearly two decades ago and had worked in road and bridge repairs for the past two years, was also among the victims, his family said. But his body has not been recovered.

Divers can no longer reach the area where they believe more vehicles — and victims — remain, so officials have moved to a cleanup operation, removing debris. Once that is complete and vehicles are accessible, divers will return to search for bodies, the police said.

One of the workers still missing is a Honduran citizen, Maynor Yasir Suazo Sandoval, in his 30s, who had been living in the United States for nearly two decades, according to Honduras’s migrant protection service. A nonprofit organization that provides services to the immigrant community in Baltimore identified another missing worker as Miguel Luna, a father of three from El Salvador in his 40s.

What about the ship and its crew?

The Dali is registered in Singapore and was headed for Colombo, Sri Lanka, according to MarineTraffic, a maritime data platform. It was carrying 4,700 shipping containers, according to Synergy Marine, its manager and operator.

The ship, which remains in the narrow shipping lane, has 1.5 million gallons of fuel and lubricant oil on board, said Vice Adm. Peter Gautier, the deputy commandant for operations for the Coast Guard, adding that 56 of the 4,700 containers still on the ship contained hazardous materials. “There is no threat to the public from the hazardous materials on board,” he said.

An inspection of the ship last year at a port in Chile reported that the vessel had a deficiency related to a set of gauges. But they were changed before the ship departed, an official said.

The ship’s 24 crew members, including two Baltimore port pilots who were directing the vessel at the time of the crash, were accounted for, and there were no injuries among those on the ship, the owners said. On board were 22 Indian citizens.

The crew members have remained on board the ship. It is normal for crew members to stay on damaged ships because they must ensure that the crashed vessel does not pose a further danger.

And the bridge?

Construction of the bridge started in 1972, and it was completed in March 1977. The bridge spanned 1.6 miles over the Patapsco River, but the crossing’s overall structure, including its connecting approaches, was almost 11 miles long. It carried about 35 million vehicles annually..

The collapse might have been avoided, some engineers said, if the pylons holding up the bridge had been better protected with blocking devices called fenders. Those can be anything from rocks piled around the pylons to large concrete rings padded with slats of wood. But the protection would have had to be able to absorb a hit from such a huge container vessel.

Pete Buttigieg, the U.S. secretary of transportation, said on Wednesday that the structure was “simply not made to withstand a direct impact” from a modern cargo vessel. He noted that ships frequenting the port today are “orders of magnitude bigger” than ships in use when the bridge was built.

President Biden said he expected that the federal government would pay for the “entire cost” of rebuilding the bridge, but the Dali’s owners could be forced to pay damages surpassing $1 billion, shipping and insurance industry experts said.

Reporting was contributed by Luke Broadwater, Peter Eavis, Jacey Fortin, Nicholas Bogel-Burroughs, Anna Betts James Glanz, Jenny Gross, Mike Baker, Miriam Jordan, Patricia Mazzei, Emiliano Rodríguez Mega Michael D. Shear, Zach Montague and Jin Yu Young.