Bodyguards have been employed to protect Wellington Mayor Kerry Prendergast after she received physical threats.
The suspect made an "abusive and threatening" call to the council call centre on Friday afternoon, police said.
"They were veiled threats against the mayor," Inspector Pete Cowan said. "It was obviously to her physical being."
Police had a good lead on who made the call, Mr Cowan told the Dominion Post.
Bodyguards accompanied Ms Prendergast to Saturday's rugby game at Westpac Stadium and would stick by her side at certain public events.
A council spokesman said security had been increased around the mayor.
"There was a threat that this person and possibly other people would come to the council to do some unspecified act," he said.
Ms Prendergast would not comment.
- NZPA
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