BALTIMORE (AP) -- Investigators began collecting evidence Wednesday from the cargo ship that plowed into Baltimore's Francis Scott Key Bridge and caused its collapse, while in the waters below divers searched through twisted metal for six construction workers who plunged into the harbor and were feared dead.
The investigation picked up speed as the Baltimore region reeled from the sudden loss of a major transportation link that's part of the highway loop around the city. The disaster also closed the port that is vital to the city's shipping industry.
Officials with the National Transportation Safety Board boarded the ship and planned to recover information from its electronics and paperwork, NTSB Chair Jennifer Homendy said.
The agency also is reviewing the voyage data recorder recovered by the Coast Guard and building a timeline of what led to the crash, which federal and state officials have said appeared to be an accident.
The ship's crew issued a mayday call early Tuesday, saying they had lost power and the vessel's steering system just minutes before striking one of the bridge's columns.
At least eight people went into the water. Two were rescued, but the other six -- part of a construction crew that was filling potholes on the bridge -- were missing and presumed dead.
The debris complicated the search, according to a Homeland Security memo described to the Associated Press by a law enforcement official. The official was not authorized to discuss details of the document or the investigation and spoke to AP on condition of anonymity.
Maryland Gov. Wes Moore said the divers faced dangerous conditions.
"They are down there in darkness where they can literally see about a foot in front of them. They are trying to navigate mangled metal, and they're also in a place it is now presumed that people have lost their lives," he said Wednesday.
Among the missing were people from Guatemala, Honduras and Mexico, according to diplomats from those countries.
One worker, a 38-year-old man from Honduras who came to the U.S. nearly two decades ago, was described by his brother as entrepreneurial and hard-working. He started last fall with the company that was performing maintenance on the bridge.
Capt. Michael Burns Jr. of the Maritime Center for Responsible Energy said bringing a ship into or out of ports with limited room to maneuver is "one of the most technically challenging and demanding things that we do."
There are "few things that are scarier than a loss of power in restricted waters," he said. And when a ship loses propulsion and steering, "then it's really at the mercy of the wind and the current."
Video showed the ship moving at what Maryland's governor said was about 9 mph toward the 1.6-mile bridge. Traffic was still moving across the span, and some vehicles appeared to escape with only seconds to spare. The crash caused the span to break and fall into the water within seconds.
The last-minute warning from the ship allowed police just enough time to stop traffic on the interstate highway. One officer parked sideways across the lanes and planned to drive onto the bridge to alert a construction crew once another officer arrived. But he did not get the chance as the powerless the vessel barrelled into the bridge.
Attention also turned to the container ship Dali and its past.
Synergy Marine Group, which manages the ship, said the impact happened while it was under the control of one or more pilots, who are local specialists who help guide vessels safely in and out of ports.
The ship, which was headed from Baltimore to Sri Lanka, is owned by Grace Ocean Private Ltd., and Danish shipping giant Maersk said it had chartered the vessel.
The vessel passed foreign port state inspections in June and September 2023. In the June 2023 inspection, a faulty monitor gauge for fuel pressure was rectified before the vessel departed the port, Singapore's port authority said in a statement Wednesday.
The ship was traveling under a Singapore flag, and officials there said they will be conducting their own investigation in addition to supporting U.S. authorities.
The sudden loss of a highway that carries 30,000 vehicles a day, and the disruption of a a vital shipping port, will affect not only thousands of dockworkers and commuters but also U.S. consumers who are likely to feel the impact of shipping delays.
"A lot of people don't realize how important the port is just to everything," said Cat Watson, who takes the bridge to work everyday and lives close enough that she was awakened by the collision. "We're going to be feeling it for a very long time."
The Port of Baltimore is a busy entry point along the East Coast for new vehicles made in Germany, Mexico, Japan and the United Kingdom, along with coal and farm equipment.
Ship traffic entering and leaving the port has been suspended indefinitely.
Speaking at a White House news conference, Transportation Secretary Pete Buttigieg said the Biden administration was focused on reopening the port and rebuilding the bridge, but he avoided putting a timeline on those efforts. He noted that the original bridge took five years to complete.
Another priority is dealing with shipping issues, and Buttigieg planned to meet today with supply chain officials.
From 1960-2015, there were 35 major bridge collapses worldwide due to ship or barge collisions, according to the World Association for Waterborne Transport Infrastructure.
A cargo ship is stuck under the part of the structure of the Francis Scott Key Bridge after the ship hit the bridge Wednesday, March 27, 2024, in Baltimore, Md. (AP Photo/Steve Helber)
Rear Adm. Shannon Gilreath, commander of the Fifth Coast Guard District, speaks in Dundalk, Md., on Tuesday, March 26, 2024, as officials announce that all six workers missing after a Baltimore bridge collapsed are presumed dead and the search for them has been suspended until Wednesday morning. Officials said that the search and rescue mission was transitioning to one of search and recovery. (AP Photo/Ted Shaffrey)
A cargo ship is stuck under the part of the structure of the Francis Scott Key Bridge after the ship hit the bridge Wednesday, March 27, 2024, in Baltimore, Md. (AP Photo/Steve Helber)
In this image taken from video released by the National Transportation and Safety Board, the cargo ship Dali is stuck under part of the structure of the Francis Scott Key Bridge after the ship hit the bridge, Tuesday, March 26, 2024, in Baltimore. (NTSB via AP)
A container ship rests against wreckage of the Francis Scott Key Bridge as dawn approaches on Wednesday, March 27, 2024, in Baltimore, Md. Recovery efforts resumed Wednesday for the construction workers who are presumed dead after the cargo ship hit a pillar of the bridge, causing the structure to collapse. (AP Photo/Matt Rourke)
In this image taken from video released by the National Transportation and Safety Board, the cargo ship Dali is stuck under part of the structure of the Francis Scott Key Bridge after the ship hit the bridge, Tuesday, March 26, 2024, in Baltimore. (NTSB via AP)
A container ship rests against wreckage of the Francis Scott Key Bridge near sunrise on Wednesday, March 27, 2024, in Baltimore, Md. Recovery efforts resumed Wednesday for the construction workers who are presumed dead after the cargo ship hit a pillar of the bridge, causing the structure to collapse. (AP Photo/Matt Rourke)
In this image taken from video released by the National Transportation and Safety Board, the cargo ship Dali is stuck under part of the structure of the Francis Scott Key Bridge after the ship hit the bridge, Tuesday, March 26, 2024, in Baltimore. (NTSB via AP)
Boats work near wreckage of the Francis Scott Key Bridge on Wednesday, March 27, 2024, in Baltimore, Md. Recovery efforts resumed Wednesday for the construction workers who are presumed dead after the cargo ship hit a pillar of the bridge, causing the structure to collapse. (AP Photo/Matt Rourke)