"There have been a few incidents like that in the past month, and that has prompted us to investigate further," Mr Singh said at the time.
Following the information about the bird poison, he was continuing his inquiries, and urged the public to "remain vigilant around their pets and to forward me all information around any suspicious activity".
Mr Singh was unsure why people would be poisoning birds in the first place, "however, people do funny, unexplainable things a lot".
"It's an ongoing investigation and the information around bird poisoning is from vets dealing with the dead and dying animals.
"Not a large percentage of missing animals have been found poisoned, that is why we are not closing the investigation, as we believe this may just be a few isolated cases separated from the main issue."
As well as cats going missing or being killed in Gonville and Wanganui East, some dogs had also been poisoned.
If you have any information to pass on, contact Whanganui police through Facebook, or call Constable Singh on 349 0689.