It reminds me of a book called Murky Woods that I used to read to the kids when they were little. These monsters invade the school at night when the kids have gone home for the day.
Macaques are common here and the population is growing because they have no predator. They are not afraid of human beings and instead of foraging in the forest, they are often found at the forest edge close to human habitats.
It is now an offence to feed them (a fine of S$250) because they become very aggressive and would harrass people or raid houses near the parks. A macaque stole my wallet while I was at the park early this year. It was a funny moment. Read the full story here.