BALTIMORE (NewsNation) — 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 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.

Miguel Luna and Maynor Yassir Suazo Sandova are presumed dead.

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 addressed their families in Spanish during the news conference, 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 the 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 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 to recover information from its electronics and paperwork and to do interviews with the captain and other crew members, NTSB Chair Jennifer Homendy said during a news conference. Twenty-three people, including two pilots, were on the ship when it crashed, she said.

The ship was also carrying 56 containers of hazardous materials including corrosives, flammables and lithium ion batteries, Homendy said. She added that some containers were breached and that a sheen on the water from those materials would be handled by authorities.

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.

Authorities have released four construction workers’ names, including Luna, a husband and a father of three originally from El Salvador. Luna, who called Maryland home for more than 19 years, was a CASA employee who left at 6:30 p.m. Monday for work, the company said.

“Our hearts ache for the families of the victims and all those impacted by this horrific accident. Sadly, we discovered that one of the construction workers involved was a longtime member of our CASA family, adding an even deeper layer of sorrow to this already grievous situation,” said CASA Executive Director Gustavo Torres.

U.S. Transportation Secretary Pete Buttigieg on Wednesday did not provide a specific timeline for the bridge’s repair but noted that the original construction took five years. He emphasized, however, that it would not necessarily take that long to rebuild.

Speaking at a White House news briefing, Buttigieg said officials are focused on reopening the port, dealing with supply chain issues, rebuilding the bridge and addressing surface transportation.

Buttigieg said he will meet with shipping and supply chain officials Thursday.

“We are going to help to get it open as soon as possible,” he said.

White House Press Secretary Karine Jean-Pierre says President Joe Biden has instructed his team “to move heaven and earth” to aid in recovery and rebuilding.

The Guatemalan Ministry of Foreign Affairs confirmed that two of the men, 26-year-old Peten Chiquimula and 35-year-old Camotan Chiquimula, were from Guatemala, according to a news release.

Honduras’ Deputy Foreign Affairs Minister Antonio García confirmed a Honduran citizen, Sandoval, was missing, The Associated Press reports.

Officials have not yet released the names of the two other construction workers presumed dead.

The vessel Dali lost its steering capability before it hit the pillar around 1:30 a.m. Tuesday. It caused the span of the 47-year-old bridge, a major link in the region’s transport networks, to plunge into the Patapsco River. The loss of the bridge is expected to snarl commuter traffic and disrupt a vital shipping port.

It’s not clear what caused the ship to crash, but Moore said the ship’s crew was notified of a power loss on the vessel before the crash. The ship’s crew also issued a mayday that allowed officials to clear the bridge of cars and save many lives, Moore said.

The National Transportation Safety Board (NTSB) is investigating what happened. Investigators have boarded Dali and recovered its data recorder, Reuters reported.

NTSB Chairwoman Jennifer Homendy told CNN Wednesday morning that the recorder will be analyzed and investigators will also examine whether dirty fuel played a role in the ship’s power loss as part of its investigation into the collision.

“Right now, we do have the data record, which is essentially the ‘black box.’ We’ve sent that back to our lab to evaluate and begin to develop a timeline of events that led up to the strike on the bridge,” Homendy told CNN, adding that more information from the black box is expected to be recovered later Wednesday.

Additionally, Homendy told CNN that interviews with crew members are set to begin Wednesday.

Homendy said Tuesday that the NTSB has to verify whether a reported power outage contributed to the crash. “Too early to tell,” she said.

Dali was involved in an incident before Tuesday’s crash. In 2016, the 900-foot-long cargo vessel hit a loading pier in Belgium and damaged the ship’s stern, according to Vessel Finder. No injuries were reported. The ship’s master and pilot were held responsible for the incident.

Federal and state officials said the crash appeared to be an accident.

Moore said Tuesday that the preliminary investigation indicates no “credible evidence of a terrorist attack.” He added that the bridge was “fully up to code” and had no structural issues.

Maryland Secretary of Transportation Paul Wiedefeld said eight people were on the bridge Tuesday when it collapsed. Rescuers pulled two people out of the water, but six others were still missing as of Wednesday morning. Those six were part of a construction crew filling potholes on the bridge.

Jeffrey Pritzker, executive vice president of Brawner Builders who employed the workers, told the Associated Press the crew was working in the middle of the bridge’s span when the crash happened. Although no bodies have been recovered, Pritzker said the six missing men are presumed dead given the time that has passed and the depth of the water.

Baltimore Mayor Brandon Scott said there’s no timeline for repairing the bridge, which is a vital throughway for Baltimore commuters and people driving up and down the East Coast.

He added that some cargo appeared to be dangling from the bridge, which spans the Patapsco River at the entrance to a busy harbor. The river leads to the Port of Baltimore, a major hub for shipping on the East Coast. Opened in 1977, the bridge is named for the writer of “The Star-Spangled Banner.”

Moore declared a state of emergency and said he was working to get federal resources deployed.

Ship traffic entering and leaving the Port of Baltimore has been suspended indefinitely. As for the collapsed bridge, roughly 1.3 million trucks crossed it each year, 3,600 a day, American Trucking Associations spokesperson Jessica Gail told AP.

Dali was headed from Baltimore to Colombo, Sri Lanka, as its final destination, according to Marine Traffic and Vessel Finder.

The Associated Press and NewsNation’s Andrew Dorn contributed to this report.