As she put the umbrella back in her car she saw the man running towards her out of the corner of her eye.
"I basically started screaming, and I can scream quite loud, so quite a few people turned out quite quickly."
The mugger snatched her handbag and raced back to his car, with Radhakrishnan in pursuit.
"I noticed that the driver's window was down so I leaned in and tried to grab my bag back, but it didn't quite work."
As the car drove off she gave it a punch.
"I was just really angry because it was so brazen. It was broad daylight and it was so in-your-face and you don't really get that in New Zealand. I was furious, and it was my favourite handbag."
There was nothing of great value to the mugger in the bag, aside from Radhakrishnan's phone and her wallet only containing about $15-$20. She also had a novel she'd just bought en route back to New Zealand.
"I'm alright now but I was a bit shaken up, probably a bit more than I realised at the time.
"Quite a lovely thing about New Zealand is that lots of people came to help and one woman stayed with me the whole hour I was cancelling cards and things like that, and the restaurant nearby let me use their phone and gave me some water."
Radhakrishnan said she only saw one person in the car -- a solidly-built, well-dressed man aged 25-35 wearing jeans and a t-shirt -- but other witnesses said they saw another person inside.
Police said in a statement they responded immediately and undertook area inquiries but the offender was not located.
The investigation into the matter was ongoing and police encouraged anyone with information to get in touch by calling the crime squad on (09) 302 6557 or Crimestoppers on 0800 555 111.