A container ship rests against wreckage of the Francis Scott Key Bridge in Baltimore, March 27. AP-Yonhap

The cargo ship that lost power and crashed into a bridge in Baltimore underwent "routine engine maintenance" in port beforehand, the U.S. Coast Guard said Wednesday, as divers recovered the bodies of two of six workers who plunged into the water when it collapsed. The others were presumed dead, and officials said search efforts had been exhausted.

Investigators on Wednesday began collecting evidence from the vessel that struck the Francis Scott Key Bridge in the previous day. The bodies of the two men were located in the morning inside a red pickup submerged in about 25 feet (7.6 meters) of water near the bridge's middle span, Col. Roland L. Butler Jr., superintendent of Maryland State Police, announced at an evening news conference.

He identified the men as Alejandro Hernandez Fuentes, 35, who was from Mexico and living in Baltimore, and Dorlian Ronial Castillo Cabrera, 26, who was from Guatemala and living in Dundalk, Maryland.

The victims , who were part of a construction crew fixing potholes on the bridge, were from Mexico, Guatemala, Honduras and El Salvador, Butler said.

Maryland Gov. Wes Moore at the news conference addressed their families in Spanish, saying, "Estamos contigo, ahora y siempre" which means, "we are with you, now and always."

All search efforts have been exhausted, and based on sonar scans, authorities "firmly" believe the other vehicles with victims inside are encased in superstructures and concrete from the collapsed bridge, Butler said. Divers are to return to search for remains once the waters are clear of debris.

Jesus Campos, who has worked on the bridge and knows members of the crew who died, said on Tuesday that he was told they were on a break and some were sitting in their trucks parked on the bridge to warm up when it collapsed.

U.S. Coast Guard Rear Admiral Shannon Gilreath said at the news conference that authorities had been informed that the ship was going to undergo the maintenance.

"As far as the engine goes, we were not informed of any problems with the vessel," he said. "We were informed that they were going to conduct routine engine maintenance on it while it was in port. And that's the only thing we were informed about the vessel in that regard."

The wreckage of the Francis Scott Key Bridge is seen in this file photo, in Baltimore, March 27. AP-Yonhap

The investigation ramped up 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 initially went into the water, and two of them were rescued Tuesday, officials said.

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," Moore said Wednesday, adding that they were also trying to navigate mangled metal.

One missing 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 year 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 miles per hour (15 kilometers per hour) toward the 1.6-mile (2.6-kilometer) bridge. Traffic was still crossing the span, and some vehicles appeared to escape with only seconds to spare. The crash caused the bridge 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 vessel barreled into the bridge.

Attention also turned to the container ship Dali and its past.

People at Fort Mchenry view a container ship as it rests against the wreckage of the Francis Scott Key Bridge in Baltimore, March 27. AP-Yonhap

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, 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 conduct 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 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. Windward Maritime, a maritime risk-management company, said its data shows a large increase in ships that are waiting for a port to go to, with some anchored outside Baltimore or nearby Annapolis.

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, which was completed in 1977, 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 Thursday with supply chain officials.

Barges, including some with cranes, were on their way to Baltimore to help remove the wreckage, Gilreath said.

From 1960 to 2015, there were 35 major bridge collapses worldwide due to ship or barge collisions, according to the World Association for Waterborne Transport Infrastructure. (AP)