Teen dies after jumping into NSW blowhole

A 14-year-old boy has drowned after jumping into a blowhole at Port Macquarie while swimming with friends.

A teen who is in a serious condition in hospital was found with a stab wound on a Sydney footpath. (AAP)

A teenage boy has drowned after jumping into a blowhole at Port Macquarie on NSW's mid north coast.

It's believed the 14-year-old was swimming with friends and jumping off rocks at Nobby's Beach on Monday morning when he struck his head, Surf Life Saving NSW said.

The boy's friends grabbed an angel ring and jumped into the water to pull the teenager, who had lost consciousness, onto a rock platform.

Paramedics performed CPR but the 14-year-old died at the scene.

Another teen, believed to be a 15-year-old friend, was treated by paramedics and taken to Port Macquarie Hospital with non life-threatening injuries.