A spokeswoman said police had identified a person of interest and were locating him to speak with him.
The man who filmed the incident said in a Facebook post that he put down his equipment and immediately offered to help the photographer.
"Dirk is fine... he has a few extra marks on his head. Someone is driving him back to the hotel and he has been to medical," he posted.
The videographer said Supercars had been working with police over the altercation.
Injured photographer Klynsmith was today suffering from a headache as he landed on Australian soil.
He said the incident stemmed from an abusive encounter with a young security guard over passing through a course transit area.
"I had an argument with a young security guard about where I was to go.
"He swore at me and threatened to take my camera gear off me.
"The chap who [pushed] me wasn't even there."
Klynsmith said he saw the same guard later in the afternoon and approached him to get his name in order to lay an official complaint about his abusive and obstructive behaviour.
Klynsmith said when the guard refused his request he tried to photograph him. At this he says a man, and several others, stepped in to shield the guard and the situation escalated into a verbal stoush.
"It all happened so quickly. Most of it was a verbal argument but that last bit was really fast and I certainly didn't expect it.
"I spun around and the next minute I got knocked out."
He was treated by St John Ambulance at the track.
Klynsmith said he filed a report with police, along with a number of eye-witnesses, and video footage.
"A security guard who saw the event unfold from a vantage point came over to me and apologised for not getting down quick enough to help," he said.
The man who allegedly pushed Klynsmith said there was more to it than what was captured on film.
"There was a whole thing beforehand," he told the Herald.
The footage has drawn outrage from the motorsport community disgusted at what happened as well as the lack of intervention by onlookers.
Those who have commented include the father of the weekend's Auckland Supersprint champion Shane van Gisbergen.
"Yeh mate,..bloody disgraceful. Dirk hope health is all good," posted Robert van Gisbergen on Facebook.