An investigation is underway after bullet holes were found in Mana leader Hone Harawira's Kaitaia electorate office.
Shots were fired through the office's front window last Thursday night, Mr Harawira told Radio New Zealand.
He said he was taking the threat seriously.
"It is a worry, I get criticisms, I get threats - I even get death threats - but when people start taking shots at your office it's a whole different ball game.
"It takes it to a completely different level and it worries me about my staff and about the whanau who come to that office to get help."