Police are continuing their investigations into two more teenagers killed in stabbing incidents. A 16-year-old was knifed in the back at a party in Manchester, while a 17-year-old was fatally wounded during a street fight in south London on Saturday. The death of the older boy, who was Sri Lankan, brings the toll of teenagers to have died violently in the capital this year to 23. The latest deaths come with the Government and police under pressure to quell fears over a rising tide of knife crime. Last month, the Home Office launched the Tackling Knives Action Programme to help keep young people on the right track. In Manchester, Connor James Black died from a single stab wound after a party. Det Supt Shaun Donnellan said Connor - who was known to the police - was stabbed in the back and had no defence. He said two knives were found and were being tested for DNA and fingerprints. Connor is thought to have attended a "rowdy party" in Harpurhey, Manchester, near to where his body was found on grass 10ft from the main road. The joinery student was rushed from the scene on Moston Lane but died on the way to hospital. Mr Donnellan appealed for information about a hooded figure seen running from the scene. He added that CCTV footage was being sifted to shed light on the murder. In Croydon, police arrested a man in his 20s in connection with the murder of a 17-year-old, of Tamil origin. Early on Saturday officers were called to reports of a group of six to eight men fighting on Sumner Road at the junction with London Road. Police and London Ambulance Service found the youth with a serious wound to the neck. He was taken to the nearby Mayday hospital, where he later died. Police are seeking a mini cab driver they believe could be a vital witness to the murder.