"You look and sound like you have only been in this country for five minutes but you seem to think you can represent us," the letter says.
"How would a foreigner ever understand the issues facing our city and our country?
"Go back to the country you came from and try it there.
"We don't need people like you telling us how to live our life.
"I am getting a bit sick of immigrants and feminists telling me what is best for me, my family and my country."
The letter, which is dated September 20, is then signed off by a "concerned Kiwi".
It comes after Rasheed's billboards had already been repeatedly targeted by vandals in Taita, Wingate and Stokes Valley.
She has publicly said that it had been saddening for her knowing her children had seen the defaced signs.
But Rasheed had maintained that the vandalism had made her even more determined to fight for inclusiveness and diversity.
This is just disgusting. Vote Shazly for Hutt City Council has lived in New Zealand for 23 years and is a New Zealand...
Posted by Chris Bishop on Wednesday, 25 September 2019
The National MP for Hutt South, Chris Bishop, also took to social media to condemn the gutless letter.
"No guts to even put his name to his racism and sexism," Bishop said.
"Just breaks my heart to see people in the Hutt behave like this.
"Kia kaha Shazly and keep your head held high. There are lots of people behind you."