Man undergoing surgery after alleged stabbing at small homeless community in Sydney's CBD

A man is in hospital under a police guard after a violent brawl broke out in Sydney's CBD overnight, leaving one man with stab wounds.

Emergency services were called to the a small homeless community near the intersection of Bathurst Street and Day Street around 11.30pm yesterday after receiving reports someone had been assaulted.

Upon arrival police found a 48-year-old man suffering from stab wounds. It's understood he was stabbed several times. 

Paramedics treated the man before he was taken to St Vincent’s Hospital to undergo surgery.

A 54-year-old man was found unconscious at the scene suffering from a head injury and taken to the Royal Prince Alfred Hospital where he is now under a police guard.

It's believed he was severely beaten up. 

Police are urging anyone with information in relation to this incident to call Crime Stoppers on 1800 333 000.\