CRIME STOPPER: The Last Place shop assistant Kristie Asplin, 34, chased a shoplifter along Hurstmere Rd before retrieving the stolen items.

Passers-by watched in astonishment as an alleged shoplifter's pants fell down while she was being chased by a shop assistant, revealing that she had gone ‘commando'.

Kristie Asplin, 34, of The Last Place in Takapuna managed to catch the woman after a 100 metre dash along Hurstmere Rd.

The alleged shoplifter had visited the store a number of times before the incident around 1pm on Friday, May 17, Ms Asplin says.

"She kept telling me that she had stuff on hold so that I would go out the back of the store. I am the only one here."

As Ms Asplin reluctantly walked towards the back of the shop, she says the woman grabbed a bag from the display and fled.

"I thought screw that, it's a $500 bag and the most expensive thing in our shop, so I chased her."

With help from bystanders on the busy shopping strip Ms Asplin managed to catch the woman and retrieve the bag.

"I said ‘don't you ever come into the shop again'.

"Everyone was laughing at her because her pants had fallen down and she wasn't wearing any knickers," Ms Asplin says.

Police arrived at the store to take a statement from Ms Asplin and arrested a woman shortly afterwards in a nearby street.

"I was a bit worried because she had a bottle of bourbon in her hand and I thought she might try to swing it at me.

"But I think the adrenaline just kicked in."

A trespass notice has been issued against the alleged shoplifter.