HALF MOON BAY (KPIX) — A rescue mission turned into a recovery operation after an 18-year-old Hayward man disappeared while in waters off Half Moon Bay Thursday afternoon.

The San Mateo County Sheriff’s Office said the young man was boogie-boarding with friends at Poplar Beach around 3:10 p.m. Thursday when he and his board went under a wave.

His friends said the board came back up without him and he was last seen face down in the water. They were unable to reach him and then lost sight of him, the sheriff’s office said.

“I feel so sorrowful for the family,” said Janet Sylvester, whose grandson A.J. Irwine, was one of the boogie boarders. Sylvester said he was visiting the beach with his friends who were teammates on the Hayward high school football team.

A.J. told his grandmother he also almost lost his life trying to save his childhood friend.

“A.J. just yelled at him to float on his back,” Sylvester said.

“Then A.J. got sucked into the undertow as well and he felt like he was drowning and he just gave up. That’s when someone from the shore grabbed his hand and pulled him in.”

The young men and family members of the missing teenager huddled together on the beach Thursday evening as officials continued their recovery mission, hampered by heavy fog.

The Coast Guard and the California Highway Patrol were assisting the sheriff’s office in the search for the unidentified man.

Officials told KPIX a Coast Guard vessel had been searching the coast for hours but so far had not found the missing man.