Baptista passed away on Thursday
The teenage suspect handed himself in at a police station on Friday and remains in custody.
Baptista was fatally stabbed in Stratford Broadway, near Tramway Avenue, on Thursday afternoon.
Stratford Centre, near to where Baptista died (credit: Google Maps)
The 15-year-old, from North Woolwich, passed away within half an hour of the attack.
A second teenager, also aged 15, was found with stab injuries and was taken to an east London hospital. His injuries are not life-threatening.
Anyone who can assist police investigating the attack is asked to call 101, quoting CAD 4644/10OCT19, or Crimestoppers anonymously on 0800 555 111.
Tags: Newham, Stratford, North Woolwich
