The U.S. Coast Guard said Thursday it is searching for a U.S. Marine who went swimming in high surf off Puerto Rico's northeast coast while on vacation, while another American tourist died in a separate incident in the dangerous surf.

Officials identified the missing Marine as 26-year-old Samuel Wanjiru from Massachusetts and said he was visiting the island with his family. He went missing Wednesday afternoon after going into the water at La Pared beach in Luquillo. Video posted on social media by Puerto Rico's Bureau of Emergency Management and Disaster Administration showed divers jump from a helicopter in search for the man.

Also on Wednesday, another American tourist died in northwest Puerto Rico after authorities said he rescued his teenage children who had been swept away by heavy surf.

"This month has been deadly when it comes to beach drownings in the area of Puerto Rico," said Capt. Jose E. Díaz, commander of the U.S. Coast Guard Sector San Juan. "People need to realize that the situation is serious enough to limit our ability to respond to search and rescue cases with surface vessels without further endangering our crews and assets. Our thoughts and prayers are with the families who have lost their loved ones to the sea, we hope they find strength during this most difficult time." 

A high surf advisory was issued late Tuesday for Puerto Rico's northwest, north and northeast coasts and will remain in effect until late Thursday, with waves of up to 12 feet (4 meters).

Díaz noted that most open ocean beaches in Puerto Rico do not have lifeguards.

In:
• United States Coast Guard
• Drowning
• Puerto Rico