A visitor died Sunday after he ran into trouble while snorkeling at Hanauma Bay. 

At about 10:13 a.m. Sunday, the man in his early 40s from Baltimore was snorkeling by himself. Lifeguards brought him to shore and performed cardiopulmonary resuscitation until paramedics arrived. 

He was transported to Straub Clinic and Hospital in critical condition. Honolulu police said he was pronounced dead at the hospital.  

Capt. James Todd, spokesman of the Honolulu Fire Department, said the visitor was traveling with his wife and was part of a snorkeling tour group. 

The medical examiner has yet to identify him.