Officers said it happened near the children’s playground in the park around 19:30 on Monday and involved two girls and a boy aged between 11 and 14.
One of the girls received minor injuries to her face, but she did not require hospital treatment.
It is believed that the children know each other.
Anyone who may have seen this or who has more information is asked to contact Police on 612612 or Crimestoppers anonymously on 0800 555 111 or via their online form.