Prime Minister Jacinda Ardern is directing the police minister to ensure officers are doing everything possible in the case of a Canterbury University academic who claims the Chinese government is intimidating her.
Professor Anne-Marie Brady claimed her office had been broken into twice, her house burgled and her car tampered with since publishing a paper on the influence of the Chinese Communist Party (CCP) last year.
An open letter with 169 signatures from overseas academics, journalists and politicians was published on the Czech website Sinopsis on Thursday morning.
The letter states: "We, the undersigned concerned scholars and others with an interest in China, have been alarmed and appalled by the recent wave of intimidation directed against our colleague, Professor Anne-Marie Brady."
It said the New Zealand government had failed to acknowledge a problem existed and was refusing to provide police protection for Prof Brady.
Jacinda Ardern told reporters the government had to be mindful of police independence, but she would ask Police Minister Stuart Nash to follow up on the case.
"What I will do is have the police minister just seek an assurance that everything that can and should be done is being done, including for Ms Brady's own personal security."
The letter called on the government to give Prof Brady protection so she could continue her research.
"These circumstances make it likely that this harassment campaign constitutes a response to her research on the CCP's influence and an attempt to intimidate her into silence."
Last week, 29 academics, researchers and human rights advocates wrote an open letter to the prime minister in support of Prof Brady.