A teenager has been stabbed in the back after refusing to hand over his phone during a fight on a bus.

The boy was approached by two other teens not known to him while he was sitting by himself waiting for a bus near Arndale shopping centre, at Kilkenny in Adelaide’s northern suburbs.

WATCH ABOVE: A stabbed teenager speaks out about his attack on an Adelaide bus.

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Jay* spoke to 7NEWS fearing retribution, and said the thieves bragged about the crimes they wanted to carry out.

He said he was harassed by the pair while waiting at the Hanson Rd bus stop in Kilkenny, one of the alleged attackers frustrated that Jay wouldn’t let him borrow his phone.

“They were talking to each other saying how they’d robbed someone before and how they don’t care, they’ll rob anyone, stab anyone,” he told 7NEWS exclusively.

Jay now requires physical therapy after his shoulder was dislocated Credit: Supplied.

The pair then also jumping on the same bus as him without paying and continued to brag about previous crimes.

Sitting near Jay, the pair wanted to know where Jay was going, and got mad that he refused to invite them along to a friend’s house.

“I pressed the button to get off and that’s when they grabbed me, and then they said ‘Give me your phone, give me everyone you’ve got’ and I said ‘Bro don’t do this come on, I just want to go home’” Jay said.

“He said ‘I will stab you, if you don’t do it.’”

To get off the bus, Jay pushed one of the other teenagers away.

Other passengers on the bus didn’t intervene, or come to Jay’s aid.

A fight to get Jay’s phone quickly broke out on the bus before he was allegedly stabbed in the back and his shoulder injured.

“I was pushed against the back chair, and that’s where I think I was stabbed,” Jay said.

The fight continued, with Jay not realising he had been stabbed and just wanting to get off the bus, defending himself against the other two teenagers.

But after another scuffle, Jay told 7NEWS that his left shoulder was then dislocated.

“He then held a knife against my stomach, he went to stab me, so I grabbed him, and pushed him away.”

The pair then yelled at the bus driver to let them out, and ran from the scene.

Jay quickly told the bus to close the doors, not wanting the pair to return.

Emergency services including police and ambulance were quickly called by the bus driver.

Only then did a couple of passengers help Jay, giving him a phone to call his mum and a bottle of water.

Jay’s mother is worried for her son Credit: 7NEWS

Jay was rushed to hospital with a wound in his top right shoulder where he was allegedly stabbed.

His mum is worried about her son’s mental health after the attack.

“I’m worried about his long-term [well-being], how it’s going to affect him mentally,” she told 7NEWS.

He has since received treatment in hospital, including stitches for the stab wound.

His arm was put back in place, with the teen now requiring physical therapy to recover from the injury.

Jay is now recovering at home.

Police are investigating the incident.

*Names have been withheld due to safety concerns.