The victim has alleged that a green Ford Ka pulled up alongside him before a man got out of the vehicle and hit the boy several times with the weapon.
The teenager sustained serious injuries in the attack including a broken arm. The man is described as being of mixed race, aged about 19, 6’2” tall and of skinny build with brown hair.
“We are appealing for witnesses to this assault,” said a spokesperson. “If you saw anything that would help with our enquiries please call non-emergency number 101 quoting log 221 of 30/09/17.”