At least four people died after a cargo ship slammed into a control tower in the Italian port of Genoa, toppling it into the harbor, rescue officials said on Wednesday.

A half-dozen other people remained unaccounted for, including some feared trapped inside the submerged elevator of the control tower, officials said.

Luca Cari, spokesman for the firefighters at the scene, told The Associated Press that the fourth body had been located in the area of the elevator and that searches were continuing.

The crash occurred at around 11 pm on Tuesday, during a shift change, making the accounting of personnel more difficult.

By Wednesday morning, all that was left of the control tower was the mangled exterior staircase, tilted to its side. The tower itself - which was located on the very edge of a dock jutting out into the harbor - was either in the water or in a heap of wreckage on the dock.

Andrea Furgani, an ambulance doctor and one of the first rescuers, said crews initially brought four injured to area hospitals in Genoa.

"The conditions were critical. They mainly suffered wounds caused by compression, broken bones and wounds on the chest," he told the AP.

The ship was the Jolly Nero of the Ignazio Messina & C SpA Italian shipping line. According to its website, the Genoa-based Messina Line has a fleet of 14 cargo ships, with the Italian-flagged Jolly Nero listed as being 239 meters long and 30 meters wide.

The ANSA News Agency quoted tearful company official Stefano Messina as saying nothing like this had ever happened before to the company, which was founded in 1921. "We are devastated," he was quoted as saying.

"It was an inexplicable tragedy," Port Authority President Luigi Merlo said.

A statement released on the Italian presidential office website said the President Giorgio Napolitano has learned the news of the deadly incident in the Port of Genoa with dismay and is anxiously waiting to learn the fate of the missing.

The Coast Guard and Port Authority both had staff working inside the tower, where a shift change was taking place when the accident occurred, meaning that more people would have been on it.

The cause of the crash was still unclear, but could have resulted from a mechanical problem, according to some experts quoted by local media.

AP-Xinhua

(China Daily 05/09/2013 page10)