Investigators are still trying to figure out what led to the death of a worker at the Port of Oakland on Monday afternoon.

The worker was operating a crane when he fell and died at the scene, U.S. Coast Guard Lt. j.g. Mark Leahey said. The victim was a crew member who served as the chief engineer aboard Portuguese ship “Albert Oldendorff.”

The vessel was docked at Schnitzer Steel Industries, a metals recycling company, but the worker was not a part of the business’ ship loading staff, company spokeswoman Jackie Ray said.

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