A man free-diving for lobsters off the coast of Nahant’s East Point died Saturday after running out of oxygen, authorities said.

Vinicius Vianna, 38, of Danvers, was diving with another man in the water near Forty Steps beach when he began to run out of air and fell unconscious, officials said. A woman called to report an unresponsive scuba diver in the water at around 4:40 p.m., CBS Boston reported.

“One was having trouble with his snorkel, so he was trying to switch back to his air tank,” Nahant Harbormaster Rob Tibbo said.

“The other diver tried to switch him over but couldn’t. There was a lot of waves out there, it was rough,” Tibbo said. The violent current had also thrown Vianna against rocks.

Vianna was said to be an experienced diver who was certified as a rescue diver, authorities said. He was taken to Salem Hospital where he was pronounced dead.

The other diver was a 41-year-old Bedford man was also taken to the hospital and treated for exhaustion.