Man fighting for life after jumping off Adelaide balcony while allegedly running from police

A young man is fighting for life after he jumped off a balcony while allegedly running from police in Adelaide's city centre.

The 20-year-old from Gepps Cross took a plunge of more than three metres outside Festival Theatre early on Tuesday morning.

"Police were investigating a theft in the city and as a result of that investigation had cause to speak to a man at Festival Plaza," SA Police Assistant Commissioner Stuart McLean said.

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Police said they approached the man about 2.15am and officers spoke with him for several minutes before he turned and ran.

"After speaking with police for several minutes, the man ran off and jumped off the balcony," a police statement about the incident reads.

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Officers rushed to perform first aid after he jumped, before paramedics arrived and rushed him to the nearby Royal Adelaide Hospital with a police escort, where he remains tonight in a fight for life.

"I'm very sorry for the nature of this and wish this individual a swift recovery," Police Minister Joe Szakacs said.

Police are now looking into whether they could have approached things differently.

It's not clear whether it is being treated as an incident in custody.

"Whenever a circumstance like this occurs there will be an investigation," McLean said.

Police are also continuing their investigation into the alleged theft officers had approached the man about in the first place.

They wouldn't reveal any details about the allegation.

In the meantime, theatre staff were left to clean up the aftermath.

"A three-metre fall's not that big but still plenty to hurt yourself," one local told 9News.

"Unfortunately, he's come off second best here."

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