Hong Kong police are investigating suspected animal cruelty after four dogs were found dead in the border district of Lok Ma Chau this week, with nine others reportedly missing.

According to police, four dog carcasses were found at a site on Liu Pok Road, Lok Ma Chau, within four days since Monday.

All were mongrel dogs, with no obvious injuries on their carcasses, police said.

In a statement on Monday, police said that a female Hong Kong resident on the Lunar New Year’s Eve reported a dead dog on Liu Pok Road and suspected that the animal had been poisoned.

Police said on Tuesday they received another report of dead dogs on Liu Pok Road, also suspected of being poisoned, and found two dog carcasses at the scene.

The force said on Thursday that it received the report of the fourth dead dog on that day.

Police said they believed the cases were related. No one has been arrested so far.

All the dog carcasses have been transferred to the Society for the Prevention of Cruelty to Animals for autopsy and toxicology tests.

Narelle Pamuk, chairperson of the Sai Kung Stray Friends Foundation, said on Facebook on Tuesday that she first found a dog named BLui dead in Lok Ma Chau on Monday after the group’s volunteers noticed 13 dogs, including BLui, were missing.

Pamuk said that when she arrived at around 3.50pm on Monday at the border site, where the stray dogs the group was feeding reside, BLui ran to her, wagging her tail.

The dog walked with Pamuk as she searched for other missing dogs but sat down suddenly. BLui suddenly screamed and ran past Pamuk at full speed into a marshland. When Pamuk found BLui, the dog was already dead.

Pamuk said she returned to the site again on Tuesday and found two dead dogs in a pond. She found the fourth dead dog on Thursday in the same pond.

“What rotten human/s could do this? The dogs were healthy, desexed, vaccinated dogs aged 3.5 years and younger, ” she said on Facebook.