A train engineer intentionally drove a speeding locomotive off a track at the Port of Los Angeles because he was suspicious about the presence of a Navy hospital ship docked there amid the coronavirus crisis, federal prosecutors said Wednesday.

The locomotive crashed through a series of barriers and fences before coming to rest more than 230 metres from the U.S. Navy Hospital Ship Mercy on Tuesday, the U.S. Department of Justice said in a release.

Nobody was hurt.

Eduardo Moreno, 44, was charged with one count of train wrecking, prosecutors said. It wasn't immediately known if he has an attorney.

Moreno acknowledged in two separate interviews with law enforcement that he intentionally derailed and crashed the train near the Mercy, according to the criminal complaint.

"You only get this chance once. The whole world is watching. I had to," Moreno told investigators, according to the complaint. "People don't know what's going on here. Now they will."

Suspect acted on his own, police say

Moreno said he was suspicious of the Mercy and believed it had an alternate purpose related to COVID-19 or a government takeover, an affidavit states. Moreno stated that he acted alone and had not pre-planned the attempted attack.

In an interview with FBI agents, Moreno stated that "he did it out of the desire to 'wake people up,'" according to an affidavit.

"Moreno stated that he thought that the USNS Mercy was suspicious and did not believe 'the ship is what they say it's for,'" the complaint said.

Phillip Sanfield, spokesperson for the Port of Los Angeles, said the locomotive never came close to the Mercy.

"It would have had to have gone several hundred yards through a parking lot and cross a water channel to reach the ship," Sanfield said. "The tracks are nowhere near the Mercy."

Small fuel leak controlled

The engineer wasn't a port employee but apparently was working for Pacific Harbor Line Inc., a train company that handles cargo in the port and connects to major railroad lines, Sanfield said. The company didn't immediately return a phone call seeking comment.

A small fuel leak was quickly controlled and port operations weren't seriously affected, Sanfield said.

The USNS Mercy is shown entering the Port of Los Angeles in Los Angeles on March 27. It is one of two U.S. Navy hospital ships being utilized to help hospitals in L.A. and New York City deal with an increase in admissions. (Mark J. Terrill/The Associated Press)

Moreno was arrested by a California Highway Patrol officer who witnessed the crash and captured him as he fled the scene. The FBI's Joint Terrorism Task Force and the Port of Los Angeles Police are now leading the investigation.

The CHP officer reported seeing "the train smash into a concrete barrier at the end of the track, smash into a steel barrier, smash into a chain-link fence, slide through a parking lot, slide across another lot filled with gravel, and smash into a second chain-link fence," according to an affidavit.

The Mercy arrived in port this week to provide a thousand hospital beds to take the load off regional medical centres expecting a surge of COVID-19 patients.