An academic in New Zealand who has warned of China’s growing influence in domestic affairs says her car was “sabotaged”, just months after suspicious break-ins at her home and university office.

Anne-Marie Brady, an expert on Chinese politics at the University of Canterbury in Christchurch, said she was informed by her mechanic that her car tyres had been dangerously sabotaged. She said air had been let out of the front tyres and the valve caps removed, adding that she believed someone “broke in to my garage to do it”.

“[The mechanic] called me, very alarmed, and said it could only be sabotage, that there is no other explanation,” she said in a tweet.

“It was not noticeable when we drove the car, but if we braked suddenly the car would have lost control.”

She added: “I seldom drive the car, but my husband and three children use it every day. Whoever did this doesn’t care about human life and thinks there is no consequences for doing it in NZ.”

Police are investigating the incident, which follows growing concerns in New Zealand about alleged attempts by China to exercise influence there.

Last month, Jami-Lee Ross, an MP from the opposition National party, released a secret tape suggesting that a prominent Chinese businessman who has close ties to the Communist party made a £53,000 donation to the party to encourage it to appoint a second Chinese-origin New Zealander as an MP.