A leak of refrigerated gas killed three people Tuesday on a cargo ship, including a supervisor investigating reports that workers were dizzy and two employees who tried to save him, authorities said Tuesday.

The victims were found unconscious in the hull of the ship, the Broward County Sheriff's Office said. The cause of death was chemical asphyxia due to inhaling argon gas, which had been leaking from a container the workers were loading.

Argon is colorless, odorless and nontoxic, but it can cause suffocation in a contained space.

The leak affected no one else, officials said. The shipping container is in a secured area of the Fort Lauderdale port.

The victims were Hayman Sooknanan, 47; James Cason, 43; and Rene Robert Dutertre Jr., 25.

Crew members reported feeling dizzy, so Sooknanan went to investigate, authorities said. A dock captain later saw Sooknanan lying on the floor and ordered the ship evacuated.

Cason then tied a shirt around his face and ran back to save his colleague. When Cason didn't return, Dutertre did the same. They were later found unconscious.

The company's owner, John Gorman Jr., said it is investigating internally.

Florida Transportation Services, which loads and unloads cargo, "follows extensive safety procedures and conducts ongoing employee safety training," Gorman said.

A woman who answered a phone at Florida Transportation Services refused to comment.

Argon is used in light bulbs, lasers and welding, but it is unclear why the ship was carrying it.

Click here for more on this story from the Miami Herald.

The Associated Press contributed to this report.