Lower Hutt dairy owner Mayur Gandhi talks about fighting off an attacker who entered his shop with a hammer and knife.

A Hutt Valley dairy owner was hit with a hammer and cut with a knife after tackling a masked robber in his shop.

Mayur Gandhi managed to fight off the 15-year-old attacker, who then fled on foot. Gandhi gave chase and drafted in the help of a passing customer who caught the teenager, and pinned him to the ground until police arrived.

The Wednesday night attack took place around closing time at 9pm as Gandhi was fetching paracetamol for his wife from his car.

SUPPLIED Mayur Gandhi lunges to wrestle the hammer from his teen attacker's grasp.

Gandhi heard his wife Sonam screaming and turned to see a figure in a red balaclava trying to force his way through the shop's door with a knife in one hand and a hammer in the other, as his wife and her assistant struggled to hold it closed.

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SUPPLIED The dairy's CCTV footage shows the teenager enter the Alicetown shop, carrying a knife in one hand and a hammer in the other.

The couple's young children were asleep upstairs above the shop.

Gandhi yelled at the man and the pair's eyes met.

"He had the hammer up in the air. I looked at him, he looked at me ..."

As he raced across to the shop, the women fell silent.

"I couldn't see my wife. I thought she had been attacked, hit."

Adrenaline kicked in, and he tackled the intruder.

"He hit me with the hammer ... He hit me about the left arm and right arm about five times and cut me with a knife."

The pair tussled in between the counter and shelves, amid the bottles of of Jif and Tip Top icecreams.

CCTV images captured Gandhi's face animated by rage as he lunged for his attacker's weapon.

"I managed to wrestle the hammer off him, and he fell down to the ground."

The teen fled down the road, and Gandhi gave chase.

He spotted a regular customer driving by, and called to him to phone the police.

The customer followed the teenager in his car to a school. The robber turned around when he got to the school, and the customer jumped out of his car and chased him back to the dairy on foot.

"The customer managed to tackle the guy and pin him down," Gandhi said.

Then the police and an ambulance arrived, by which time Gandhi realised his shirt was stained by his blood.

"At the time I couldn't feel a thing."

He was taken to hospital, where he had seven stitches in his side.

Gandhi works in insurance, while his wife runs their Railway Ave dairy, Mayur Foodmart. They live above the shop with their young children.

He said he was "pretty pissed off" about what happened.

His wife was unhurt, but badly frightened. "She is still pretty shaken up about it.

"It's affected my wife, more than anything, that somebody would try and do this. We have worked really hard for this and someone would try and rob us."

They later learned the teenager, who was taken away by the police, was just 15. That saddened Gandhi, as a father himself.

"I was thinking about myself at 15. Star Wars was my favourite movie.

"It's not the way a 15-year-old should be living. He should be enjoying his youth."

Sonam Gandhi said she was left questioning why she and her husband had been targeted.

"If we are giving to others, why do we get treated like this?

"I want the thief to get punished. He may not have taken anything from here, but he can't put someone's life at risk."

She was worried about her family's safety. "I am scared, we are going to keep three people inside the dairy in the evening now.

"I am scared as soon as we open at 6am. I have said we should sell and leave.

"If something happened to me, it's OK; if something happened to my husband, we'll be OK; but what if something happened to my children?"