BALTIMORE (AP) — Federal prosecutors announced criminal charges Tuesday in the 2024 collapse of Baltimore's Francis Scott Key Bridge, accusing a Singapore-based ship operator and a senior employee of making critical decisions that caused a vessel to crash into the span, killing six people, and covering up what happened.

Acting Attorney General Todd Blanche called it a "preventable tragedy of enormous consequence."

The indictment names Synergy Marine Pte Ltd., based in Singapore, and Synergy Maritime Pte Ltd., based in Chennai, India. Radhakrishnan Karthik Nair, 47, an Indian national who was technical superintendent for the Dali container ship, was also charged.

The Dali, bound for Sri Lanka, lost power twice in a four-minute span as it moved to sea from the Port of Baltimore, causing it to crash into the Key Bridge on March 24, 2024. Investigators say a loose wire in a switchboard likely caused the first power loss that caused its steering to fail.

After regaining power, the ship found itself in trouble again. The Dali turned to a certain pump to supply fuel to two generators but the pump was not designed to automatically restart after the first blackout, so a second blackout occurred, the indictment says.

The ship crashed into a supporting column of the bridge at about 1:30 a.m.

If the Dali had used the proper fuel pumps, according to the indictment, the vessel would have regained power in time to safely get under the bridge. It crashed instead, killing six construction workers who had been filling potholes.

"As alleged, the bridge was struck and collapsed because those who were responsible for the ship's operation deliberately cut corners at the expense of safety," said Jimmy Paul, head of the FBI's Baltimore office.

The companies and Nair are charged with conspiracy, willfully failing to immediately inform the U.S. Coast Guard of a known hazardous condition, obstructing an investigation by the National Transportation Safety Board and making false statements. Messages seeking comment about the indictment were not immediately returned.

The Synergy companies are also charged with misdemeanors for the release of pollutants into the Patapsco River, including shipping containers and their contents.

The FBI's investigation focused on the vessel's operations and whether the crew knew of critical systems issues before leaving port. The NTSB found that the two electrical blackouts disabled the controls of the huge cargo ship before it crashed into the bridge.

The ship had experienced two blackouts in port a day earlier, but Synergy didn't investigate or report those as required and provided false information to the NTSB, the government alleges.

Maryland officials estimate it could cost between $4.3 billion and $5.2 billion to replace the bridge, which is expected to be open to traffic in late 2030.

READ MORE: A year after the Baltimore bridge collapse, a long road to recovery is ahead

"The altered skyline is a constant reminder of this tragedy," Paul said.

But the true cost of the collapse was far greater, according to the Maryland Attorney General's Office. It halted shipping at the Port of Baltimore, disrupted the livelihoods of thousands, rerouted road traffic through communities already bearing disproportionate burdens and triggered economic problems statewide.

The indictment comes on the heels of a settlement in principle between the State of Maryland, Synergy Marine and Grace Ocean Private Limited, the Singapore-based ship owner, Attorney General Anthony Brown announced in April.

That lawsuit alleged the crash was the result of negligence, mismanagement and the reckless operation of a vessel that was not seaworthy and should never have left port. Plaintiffs include the families of the six construction workers who died, owners of cargo that was on the ship and local governments seeking damages for economic losses. The details of the settlement haven't been disclosed and some portions of the lawsuit remain unresolved.

The state sought damages on behalf of its agencies for the destruction of the bridge, harm to the Patapsco River and surrounding environment, lost revenues and economic losses to Maryland and its residents.

The settlement does not resolve any claims the state has against the shipbuilder, Hyundai, the attorney general's office said in April.

The bridge, a longstanding Baltimore landmark, was a vital piece of transportation infrastructure that allowed drivers to easily bypass downtown. The original 1.6-mile (2.6-kilometer) steel span took five years to build and opened to traffic in 1977.

White reported from Detroit.