SYDNEY, April 20 - Ali Mosawi, 17, was pulled out of sight by treacherous surf on Saturday afternoon while swimming with his brother and three cousins at the unpatrolled Pebbly Beach north of Coffs Harbour.

The five young men had been waist-deep in the water when they got into trouble with only four making it back to the shore.

The group had only just arrived from Sydney for an Easter weekend camping trip in the Yuraygir National Park.

Around 30 family members have since been keeping vigil at the beach and plan to remain there until Mosawi's body is found.

During the initial search, the Westpac rescue helicopter, PolAir, jet skis, drones, police divers and Surf Life Saving NSW volunteers all scoured the area.

But the recovery operation has now been scaled back to water police and lifesaving volunteers, a NSW Police spokeswoman said.

Ali was a student at Miller Technology High School near Liverpool in Sydney's southwest.

Support is being arranged for his devastated peers upon their return to school after the Easter holiday break.

In a tribute posted to Facebook, friend Ali Alzameli said: "Love and miss you brother. See you in the hereafter."

"Please pray that they find his body," he said.

Any decision to abandon the recovery operation will be made after consultation with Mosawi's family.

AAP