A teenager was fatally stabbed on a bus in Stratford after “school beef chat” on social media, a court has heard.

Baptista Adjei, 15, was fatally attacked as he travelled with a group of friends on the afternoon of October 10 last year.

When the bus pulled up, a youth boarded wearing a blue latex glove and carrying a “vicious looking” hunting knife, the Old Bailey heard.

The youth attacked Baptista with the 10in long blade, stabbing him in the chest twice, puncturing his lung and heart, jurors heard.

Mortally injured, the St Bonaventure’s pupil got off the bus and ran away but collapsed on the ground near a McDonald’s restaurant.

Another boy was also stabbed in the arm and leg but survived, jurors were told.

He later told police that the stabbing had followed some inter-school banter on Snapchat a couple of weeks before.

He said the “school beef chat” had started out in fun ahead of a football match.

A youth had sent Baptista a message saying: “If you’ve got no bodies on your blade, leave the group chat,” the court heard.

Baptista, from North Woolwich, allegedly replied: “Shut up. You’ll be the first.”

The youth who had allegedly sent the message to Baptista is one of two 16-year-olds from east London on trial for his murder.

Prosecutor Crispin Aylett QC said the teenager who wielded the knife had admitted the manslaughter of Baptista and unlawful wounding of the other boy.

But he has denied the more serious alternative charges of murder and wounding with intent.

Mr Aylett said: “The prosecution suggest that in stabbing Baptista twice in the chest in each case to the depth of 12cm (5in) and puncturing separately the lung and heart, you may think (the defendant) must have intended at least to cause Baptista really serious harm.

“The knife that had been used was found to have a blade that was 10in or 25cm long.”

The second defendant accepted he was on the bus, having tapped in with his Oyster card and been caught on CCTV, the court heard.

Mr Aylett said the case against him was that he “tipped off” the other defendant knowing what he was going to do.

He added: “In other words they were in this together.”

The second defendant denies all the charges.

The trial continues.