Two cats have died of injuries which a cat welfare group said are similar to those inflicted on at least three others in the same area since September last year.
The latest incidents were highlighted last Saturday on a Facebook page, Yishun 326 Tabby cat, which appealed for information and witnesses to the suspected animal abuse.
The day before, an employee of Northland Primary School in Yishun Avenue 4 had found a seriously injured cat on the school premises at about 7.30pm.
She alerted caregivers at the Cat Welfare Society (CWS), who immediately rescued the animal and took it to a Mount Pleasant animal clinic.
According to CWS, the vet said there had been trauma to the spine arising from a direct hit or kick.
The animal did not survive.
The other cat was found about 2km away from the first, near Block 281 in Yishun Street 22, next to Yishun Neighbourhood Park.
"We are aware there's someone going around to (the) different spots in Yishun to kill cats," the Facebook post said.
CWS told The Straits Times that it believes the recent cases are linked to a series of cat deaths that had been reported in the neighbourhood.
Since September last year, at least three other cats have been found beaten to death, with injuries to their paws and spines.
Those three were all found near Northland Primary.
CWS chief executive Joanne Ng said society members have been patrolling the blocks next to the school over the past few nights.
The society also said it has identified a male suspect and made a police report.
It said officers from the Agri- Food and Veterinary Authority were dispatched to warn the man, though the authority was unable to respond to queries yesterday.
"There's a definite trend of animal abuse cases islandwide. We've seen numbers increasing, with people writing in to us almost every day to report cases of cats found dead, injured or suspected of abuse," said Ms Ng.
CWS believes the five dead cats are just the tip of the iceberg.
In 2012 and 2013, a number of cats were found mutilated in Yishun, which led Law and Foreign Minister K. Shanmugam, who is an MP for Nee Soon GRC, to appeal to residents to identify the culprit.
The society is working with police to review footage from closed- circuit television cameras installed near the entrance to the primary school.
Ms Ng said more CCTV cameras will soon be installed in the area after approval was given by the MP for Nee Soon South, Dr Muhammad Faishal Ibrahim, last week.
The Facebook post has been shared more than 560 times with over 130 comments.