'Worst case scenario': Surfing world in shock over horror big wave accident

Big wave surfer Alex Botelho has been rushed to hospital after a serious accident at Nazare in Portugal.

The Portuguese surfer was competing in the Nazare Tow Surfing Challenge on Tuesday at one of the most-feared breaks in the world.

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He was being towed back to shore on the back of a jet-ski when he was sandwiched between two crashing waves.

Terrifying video shows an unconscious Botelho being thrown around by the huge waves before rescuers manage to retrieve him while face down in the water.

Onlookers rushed to his aid as he reached the beach before he was rushed to hospital.

"Alex Botelho was involved in a very serious incident during the Nazare Tow Surfing Challenge," The World Surf League said in a statement after the incident.

"He was rushed to the hospital and is currently stable and conscious. We are wishing Alex a full and speedy recovery.”

Nazare’s the world’s most dangerous surf

Nazare is world-renowned for its massive and terrifying breaks.

"If you take Jaws, Puerto Escondido and Waimea shorebreak and put them all on steroids… you get Nazaré,” US surfer Garrett McNamara said recently.

This is the first time the Tow Challenge has been part of the World Surf League's Big Wave world tour.

It involves surfers being towed by jet-skis into massive breaks that are normally unreachable by paddling.

Surfing fans sent their well-wishes but many questioned the necessity of the dangerous event.