Two men have been arrested on suspicion of murder after a 16-year-old boy was chased and stabbed with a machete in Camden.
On Wednesday, a 23-year-old man and an 18-year-old man were arrested on suspicion of murder. They remain in custody.
A post-mortem examination conducted on Thursday found Alex died from a stab wound to the chest.
Witnesses to the attack said the teenager banged on doors screaming "Help me, help me" during the attack at 11pm on Monday but was said to have been turned away by terrified locals.
His death marks the 90th murder inquiry opened by Scotland Yard so far this year. Fifteen of those victims have been teenagers, 14 of whom were fatally stabbed.
Neighbours today told of the distressing scenes as the boy was pursued into the estate of family homes before being attacked.
Rosanara Begum, 55, said on Tuesday: “The boy was running away from them. Then we saw the two boys holding him and the other one stabbing him.
“As soon as I heard ‘Help me, help me’ I was on the phone to the ambulance. He was bleeding a lot.
"The attackers were skinny and just looked like teenagers. They were running off and they were screaming and laughing."
Her daughter added: “We saw three boys all wearing hoods all covered in black, the middle one had a long black machete type knife. It was really long."
Detective Inspector Jamie Stevenson said: “We’re still keeping an open mind concerning the motive of this brutal attack and thank those who have come forward and spoken to us so far.
“We know there are individuals out there who can assist this investigation and we continue to appeal for those people to make contact with officers.
Please do the right thing and come forward, anonymously if need be, but do make the call.”
Anyone with information that could assist the investigation is asked to call the incident room on 020 8358 0400 quoting Cad 8433/12Aug.
