Racist harassment of a West Auckland family that included having their car tyres slashed and dead animals put in their letterbox has "shocked and surprised" a local councillor.

Henderson-Massey local board deputy chair Peter Chan wants to meet the family to offer support after they endured five weeks of torment.

The community is now rallying around the terrified family and posting their support on a community Facebook page.

"This is horrific, I'm a local in Massey also and if this family needs any support I'm always keen to help out," one user wrote.

"This kind of stuff needs to stop even if it is young teenagers ... that's pathetic these people are being threatened in the one place they should feel safe."

"Scumbag doing this is a disgrace to our community," another user said.

The campaign of hate began on May 26 when a car parked in the family's garage in Massey and another out on the street had their tyres slashed.

The mother, 35, who moved to New Zealand from South Korea a year ago and asked not be identified because of safety concerns, said she notified police but they had told her it was probably just mischievous teenagers.

She then put up CCTV cameras that caught the perpetrators on June 4 tagging a white car parked on the street with red spraypaint.

On June 11 and June 16, CCTV footage caught people leaving a dead mouse and then a dead pigeon in the family's letterbox. On Sunday, a threatening letter was placed in the letterbox that horrified the mother.

"Get the f*** out of my country motherf***** before I exterminate you myself, your cat eating son of a b***," the letter said.

Despite the CCTV cameras, police are yet to find the culprits.

Chan said the persecution shocked him, and he hadn't heard of anything like it recently.

"We have been working hard to promote diversity," he said.

"When I read this I was absolutely surprised and shocked."

The woman did the right thing contacting police and getting help from neighbours.

"I would like to visit the family if they agree and try to help them get help."

He said he could connect the family to members of the Korean community and help them tap into other resources, like the neighbourhood watch.

"I still believe this is a peaceful country and people enjoy working together," he said.

The mother of the harassed family said police came to her house after the threatening letter was left in their letterbox, bringing four cars and police dogs.

"But I do not understand why they could not find the guy. I still have not heard from the police about my case," she said.

Waitakere Area Commander Inspector Stefan Sagar said they have spoken with the family and carried out a number of inquiries.

"We will be continuing our inquiries, which will include speaking with neighbours on the street," Sagar said.

"We would like to reassure the public that police take matters of this nature seriously and will do everything we can to hold whoever is responsible to account.

"Police have spoken with the individuals concerned, have carried out a number of inquiries, including canvassing CCTV footage and undertaking a forensic analysis from the scene."

The family, made up of the mother, her husband and two preschool children, live in an otherwise quiet area of Massey, West Auckland.

They moved to New Zealand a year ago after hearing great things about the country, including its low rates of crime.

However, after a year without any hassles, the family is now on edge after being targeted in recent weeks.

"I feel so worried and threatened. If it was just one or two times, then I could move on," the mother said.

"I do worry about my family's safety. I am a mum."

The mother said neighbours on the street had comforted them after the attacks, and some checked on them each day to see that they are okay.

If anyone has information that could assist police, they should call Massey Police on (09) 839 0600 or Crimestoppers anonymously on 0800 555 111.