Two more teenagers have been 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.

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.

Detective Superintendent 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.

Speaking near the scene as they placed flowers in his memory, brother and sister Jordan and Kirsty Scullion spoke of their shock.

Miss Scullion, 18, a beauty therapy student, said: "He was a loveable lad who was never really in trouble.

"Someone told me that Connor was thought to have said something to someone which he denied.

"It all then got out of hand and there was a commotion and he ended up getting stabbed.

"He wasn't the sort of lad who would look for trouble but he would back himself up."

Mr Donnellan said: "Connor was a member of a loving family though he was known to the police, but not for anything serious.

"As of yet there is no motive but it is very early days."

Mr Donnellan 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.

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.

Police are seeking a mini cab driver they believe could be a vital witness to the murder.

Meanwhile, two men are in a critical condition in hospital after two other attacks on Saturday.

A 26-year-old in Bolton was assaulted by two men as he was chased down an alleyway behind Tavistock Road.

And a 25-year-old was assaulted between near a taxi rank in London Road in Hazel Grove, Cheshire.

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