A 17-year-old boy who died after he was shot in the head and chest has been named by police.
Sylvester Akapalara, from Streatham in south-west London, died in the fourth floor stairwell at Heron House on the Pelican Estate in Peckham on Wednesday.
Two other teenagers suffered stab wounds but have both since been discharged from hospital
Friends paid tribute to Sylvester, who was also known as Sylvester Da Donappa, on social networking websites. More than 760 people joined a Facebook group set up in his memory, showing photographs of the teenager, whose nickname was Vester, posing in jeans and T-shirt and a suit.
He was described as a "star in the making", a sportsman who went to church and spoke with a distinctive African accent.
Iheb Fehri, 18, said: "Sylvester helped me through my first steps of training, he helped me lift my first weight - 75kg. He was an amazing guy, an amazing talent. He did not deserve this, he never did any of that bad stuff, always tried to help everybody. May you rest in peace."
Herne Hill Harriers lists Sylvester and his times in track and field meetings at the Tooting Bec track in south London. In June 2007, he is listed in the Under 15 boys 200m category with a time of 24.1 and in August this year, he took part in the England Athletics Outdoor Championships at Bedford International Stadium where he ranked eighth in the 400m heats.
The black youth, the 19th teenager to die violently in the capital this year, was seen banging on the front door of one flat as he tried to escape his attackers.
A 17-year-old boy was found with a stab wound in nearby Gannet House on the same estate, and an 18-year-old man also attended hospital with stab wounds. Detectives are linking the three and have appealed for witnesses to come forward.
Five teenagers in total have been arrested in connection with the investigation. A 17-year-old and an 18-year-old have been released with no further action, while another 18-year-old and 17-year-old are being held in police custody. A 17-year-old has been bailed pending further inquiries.