Officers have appealed for anyone with information to contact them.
“We know this happened in a busy area during the day and there were likely people around,” said Detective Inspector Kelly Allen, who is leading the investigation.
“The suspect is believed to have fled the scene and I would urge anyone who saw anything suspicious in the Stellman Close area around 4pm to contact police.”
Detective Superintendent James Conway added: “The death of a child is devastating and my first thoughts are with his family and friends.”
Anyone with information is asked to call 101 quoting CAD 5387/23Jul or call Crimestoppers anonymously on 0800 555 111.
