• CONFRONTING CONTENT WARNING 

A teenager is fighting for life and another man has been seriously injured after a stabbing left pools of blood on the floor at an Adelaide shopping centre during Black Friday sales. 

Police and paramedics responded to reports of a fight inside the food court of the Elizabeth City shopping centre in Adelaide's northern suburbs, just after 2pm on Friday.

SA Police confirmed that a 20-year-old was stabbed in the abdomen and a 16-year-old boy was stabbed in the leg during the incident. The 16-year-old is fighting for life. 

A man was arrested at the scene and is now being interviewed by police. His identity is yet to be confirmed.

During a press conference on Friday afternoon, SA Police confirmed the disturbance wasn't 'a random incident'.

They also confirmed detectives had obtained the knife used in the attack.

Police said they are still searching for a fourth person who was part of the group involved in the brawl.

Superintendent Amit Sareen said: 'The injuries sustained by the 16-year-old boy are considered life-threatening.'  

The incident is believed to be a stabbing, with what appears to be blood on the floor

The incident is believed to be a stabbing, with what appears to be blood on the floor

Superintendent Amit Sareen said the teenager had life-threatening injuries

Superintendent Amit Sareen said the teenager had life-threatening injuries

Police and paramedics responded to reports of a fight inside the Elizabeth City shopping centre in Adelaide's northern suburbs, just after 2pm on Friday

Police and paramedics responded to reports of a fight inside the Elizabeth City shopping centre in Adelaide's northern suburbs, just after 2pm on Friday

'This was not a random attack. We understand the members of the group were known to each other,' he said.

Police swarmed the Elizabeth City shopping centre on Friday

Police swarmed the Elizabeth City shopping centre on Friday

In a video circulating online, a woman can be heard shouting for help as she holds up a person who appears to have been injured. 'Give me a trolley, give me a trolley now,' she screams, gesturing to other shoppers.

Pools of blood could be seen on the floor in the confronting video.

A witness told the ABC she fled the commotion. 

'We were sitting down and I was feeding my daughter and all of a sudden we just seen a whole bunch of people surrounding one guy and one guy jumped on another and it was chaotic,' she said.

'We didn't see anything [in terms of a weapon] but there was a lot of shouting and everything like that and we just got up and walked away.'

She said she then took refuge in Big W, which was located nearby.

'We didn't see anything [in terms of a weapon] but there was a lot of shouting and everything like that and we just got up and walked away.'

Anyone who witnessed this incident or has any mobile phone footage is asked to approach police at the scene or provide their details via Crime Stoppers.

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