A 14-year-old boy who died after he was attacked in Gateshead "had his whole life ahead of him" and his death has "left his family utterly devastated", police have said.
Northumbria Police found Tomasz Oleszak with injuries "consistent with having been caused by a bladed article" in the Aycliffe Crescent area of the town's Springwell Estate at just after 8pm on Monday.
A murder investigation was launched after the youngster died in hospital in the early hours of Tuesday and a 14-year-old boy was arrested.
The teenager, arrested on suspicion of murder, remained in custody on Wednesday morning, along with a 13-year-old girl who was arrested on suspicion of assisting an offender.
Chief Superintendent Helena Barron, of Northumbria Police, said: "Tomasz had his whole life ahead of him and this tragic incident has cut that life short and left his family utterly devastated.
"Their grief is unimaginable and they are in the thoughts of everyone at Northumbria Police as we continue to support them in every way we can.
"The investigation is very much ongoing and I want to thank the Springwell Estate community and everyone who has come forward with information for their support."
Ms Barron added: "While incidents of this nature are rare in our region, we do recognise the impact they have on the lives of those involved and the wider community.
"When they do occur we are committed to bringing those responsible to justice."
She said: "Officers will remain in the area over the coming days and I urge anyone with information or concerns to speak to them.
"Once again, I want to reiterate my plea to the public not to speculate on details of the investigation.
"What might seem like an innocent comment or post on social media to you could in reality disrupt an ongoing investigation and cause further upset to the family of the victim.
"We would ask that if you did see something or have information in relation to what has happened, please come forward directly to officers."
Tomasz is understood to have been a keen and talented footballer.
Gateshead Cleveland Hall Community Football Club said in a statement: "As a club today we are very devastated to hear that one of our young football players has lost his life.
"Our thoughts and prayers go out to his family, friends and anyone that knew Tomasz."
And in a GoFundMe page set up in his memory, one of the boy's coaches said: "Tomasz was a very kind, caring young man. He was brought to the UK by his parents for a better life and didn't deserve what has happened to him.
"He was liked and loved by many. He was a very passionate footballer who we all had the pleasure of coaching.
"He was much-loved member of his local community and will be sadly missed by all who loved him.
"This is every parent's worst nightmare come true and can't imagine what they're going through."
The appeal aimed at supporting Tomasz's family had raised almost £12,000 by Wednesday morning.
Northumbria Police and Crime Commissioner Kim McGuinness said on Tuesday: "It's devastating that our region has lost another young person to serious violence, and my thoughts are with the victim's family, who will be experiencing unimaginable pain."
A card left with flowers at the scene read: "To Tom, words can't even explain how much my heart broke when I found out you were passed away. You were an amazing friend to many and we all loved having you as a friend. You had the best music and the most contagious smile. You are loved and missed by many."
Another said: "Dear Tom, I'm so sorry you had to pass in the way that you did. I'm just glad you're no longer suffering."