Gelbart called police as the alleged offender began grabbing jewellery before recording video of the incident on his phone.
”I couldn’t quite believe what I was seeing, and then he started dousing the counter with petrol,” Gelbart said.
“He kind of gestured toward me with the petrol bottle, as if like, don’t come near me. I don’t think he expected to see me in the store.
“So when he made an exit, that’s when I decided, we’ve got to go after this guy.”
He then chased the man out of the store.
“As I was chasing him I was saying ‘get down, get down’,” he said.
“He had a look behind, saw me, saw me chasing him, I tried to sound as intimidating as possible.”
Two off-duty officers happened to be pulling up outside the shopping centre as the alleged thief ran outside with Gelbart in tow.
“I had some serious luck – two undercover police officers pulled up, sort of wedged him between a little bit of a ditch, and that’s when they detained and arrested him,” Gelbart said.
The man has since been charged with robbery armed with an offensive weapon and was refused bail.
Police are looking for a woman believed to be an accomplice to alleged jewellery heist.
She is believed to have driven away from the scene in a red Hyundi i30 with the bag of stolen jewellery.