Two men have been charged over an alleged triple stabbing in the Adelaide CBD that left three people in hospital.

Emergency services were called to a hotel on Morphett St at just before 5am on Monday following a report of an assault.

Police arrived to find two men and teenager with stab wounds.

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WATCH ABOVE: Three people seriously injured after triple stabbing in an Adelaide CBD hotel.

The 16-year-old boy received injuries to his back, thighs and hands.

A 27-year-old man from Craigmore sustained a laceration across his chest, and a 31-year-old Murray Bridge man suffered a laceration to his head and wounds to his abdomen.

All three were taken to hospital in a serious, but stable condition.

The 27-year-old from Craigmore has since been arrested and charged with affray and four counts of assault.

Another 25-year-old man from Fulham Gardens was arrested and charged with affray and assault.

Both men were refused police bail and will appear in the Adelaide Magistrates Court on Tuesday.

South Australia Police said the people involved are all known to each other and that it was not a random incident.