An abalone diver died Sunday near Sea Ranch after apparently suffering a medical emergency just minutes after entering the water.

The 38-year-old San Francisco man, whose name was not released pending the notification of relatives, complained of being extremely tired moments after entering the ocean, according to the Sonoma County Sheriff?s Department.

The man?s two companions swam him to a rock about 100 yards from shore and pulled him out of the water. The man quit breathing, and his friends administered CPR and shouted for help, according to reports. A fisherman passing on shore spotted them and called 911.

Rescuers called the the sheriff?s helicopter, which flew the man to shore. Paramedics were unable to resuscitate him.

The death was the seventh this year related to abalone diving on the North Coast. An Arizona man died two weeks ago near Sea Ranch after becoming caught in kelp.

At least two of the abalone-related deaths are suspected of being caused by heart attacks.

Last year, heart attacks also were suspected in at least three of seven abalone-diving-related deaths on the North Coast.