Police cordoned off a section of Hallsville Quarter in Hallsville Road after a knife attack on Saturday (March 1) at about 8.35pm.
At the scene a 17-year-old boy was found with stab injuries.
He remains in hospital in a critical but stable condition, the Metropolitan Police said.
Six people have been arrested in connection with the investigation.
A crime scene also remains around the residential area near the Tian Tian Market and Lidl shops.
Bloodstains can be seen on the floor as items are scattered around across the crime scene.
Anyone with information is asked to call police via 101 quoting CAD 6234/01Mar.
