The 59-year-old man was spearfishing with a friend when the shark struck and bit his thigh in Australia’s Great Barrier Reef

A man is fighting for his life in hospital after suffering ‘catastrophic’ injuries from a shark attack.

The 59-year-old is undergoing emergency surgery after the deadly shark ripped into his thigh in Australia’s Great Barrier Reef.

He had been spearfishing on a boat with a friend on Britomart reef, north of Brisbane, when disaster struck, according to local news reports.

Authorities described his condition as critical with catastrophic bleeding.