This photo shared on Instagram shows the photo of a dog owned by a woman who is believed to have killed her other two dogs by throwing them out of her apartment window. The text says, "Two were thrown outside the window of ninth floor, fell onto a parked car and died. This one survived." (Instagram)

South Korean police on Thursday said they were investigating a woman in her 30s on suspicion of killing her two dogs by throwing them from her ninth-floor apartment.

The suspect is believed to have thrown two of her dogs out of her apartment window at around 7 a.m. on Monday at Bupyeong-gu, Incheon, according to Incheon Samsan Police Station. Officers arriving on the scene found the bodies of the two dogs on the site.

The suspect has a history of mental illness and has been institutionalized with the consent of the family, Police plan to summon her for further questioning.

Killing an animal without justifiable cause is punishable by up to three years in prison or 30 million won ($22,800) in fines, by the Animal Protection Act.

The incident was publicized when an official of a local animal shelter posted about the incident on Wednesday. The person explained that after the two dogs fell to their deaths, another dog, which was not thrown, was found wandering around the apartment stairs, terrified.

"Despite surviving the odds, this dog is likely to return to the arms of the animal abuser. ... I wanted the public to know, so that (the dog) can go to someone who can care for it," the person wrote.

South Korea recently revised the Animal Protection Act to increase the maximum punishment from two years in prison to three years. But there is no legal clause allowing the authorities to confiscate an animal from its abuser, or prohibit the perpetrator from owning animals in the future.