The car driven by the offender was believed to be a 2010-2012 model, the spokesperson said.
"It has black alloy wheels and a distinctive chrome strip around the windows, and had no registration plates attached."
The offender was described as a teenager of average height.
"He was wearing a light-coloured hoodie and had his face covered."
Police are seeking sightings of the car involved, both before and after the incident.
Anyone who recognises the description of the car, and who has seen it around the Masterton area – particularly around the time of the aggravated burglary – is asked to contact Police, the spokesperson said.
"We are also aware there may be witnesses to the incident who we have not yet spoken to, and we'd like to hear from them too."
Earlier this week, three masked men brandishing hammers robbed a jewellery shop in broad daylight in the middle of Christchurch, making their getaway in a stolen vehicle.
The brazen bandits carried out the smash-and-grab raid just before lunchtime on Monday and were captured on security camera.
Images released by police show three males all disguised in black, armed with hammers and carrying bags for the loot.
The target was a well-known jewellery store, Petersen Jewellers on Papanui Rd in Merivale, near Bealey Ave.
Do or Dye hair salon owner Celine-Marie Lamberton works directly next door to the jewellers and said she was first alerted to the robbery by a loud noise.
"Then I just heard smashing, yelling and screaming," she added.
She said her hairdressing client grabbed her and they went to the back of the shop away from the windows.
"I looked up and this big tall guy - he must have been the last guy because there were three - walking in all covered in black," she said.
Last Friday evening, a group of men ran into Westfield Albany in Auckland and smashed cabinets at the Michael Hill Jewellery store.
A witness said they heard a loud bang near the food court just before 7pm, then saw "hundreds of people" running out of the mall.
In new footage, the thieves with balaclavas and gloves on can be seen smashing multiple jewellery cabinets with ease.
Several shocked and alarmed shoppers then follow the robbers, filming them as they exit the mall through an entrance quite close to the Michael Hill Jeweller shop.
Hundreds of shoppers had already fled the scene.
Police had said they would continue to have focused foot and vehicle patrols around retail shopping centres and malls as the school holiday period continues.
Information can be provided through police's 105 phone service or online at https://www.police.govt.nz/use-105.
