A mother who tried to save the life of a 17-year-old girl stabbed to death in east London was "shocked" by the amount of blood, her husband has said.
Teresa Farenden, 49, heard screams in the park and rushed to give first aid to Jodie Chesney, putting her in the recovery position.
But Jodie died at the scene in St Neot's Road, Harold Hill, at about 21:30 GMT on Friday.
Police have urged potential witnesses to come forward.
Mr Farenden, 54, said when his wife got to the scene she "asked if everything was alright and one of the boys said, 'no, my girlfriend has been stabbed'".
Jodie was described as a "bundle of joy and such a good person" by one classmate, with another telling BBC News: "She was so beautiful - inside and out.
"She was kind, wouldn't hurt anyone and would do anything to make anyone happy."
He added: "She put her in the recovery position and waited for the ambulance to turn up. I think she tried to resuscitate her.
"She is dealing with it better than she was last night. She was shocked with the amount of blood there was.
"Normally you do not see anything like this in the park.
"Hopefully they will get someone for it. This just should not happen."
Jodie's family have issued an appeal on social media for witnesses to the attack.
Her grandmother, Debbie Chesney, wrote: "How have we come to this point where kids can't have a walk in a park without suffering an unprovoked attack?
"If anyone knows anything about this please contact the police with information.
"We don't want anyone else to go through what our family is suffering right now. This has to stop, there are too many young people having their lives cut short by needless violence."
Police sealed off the area, known locally as Amy's Park, and conducted forensic searches, but no arrests have yet been made.
Shocked locals have left tributes, flowers and messages at the scene.
The teenager's death comes less than a week after 20-year-old Ché Morrison was stabbed to death outside Ilford train station in east London.
While Jodie is the first teenage girl to die in a homicide in the capital this year, she is the 18th person to be killed in London in 2019 and the fifth teenage death.
Last year, two 17-year-old girls and one 18-year-old woman were murdered in London.
Acting Det Ch Supt John Ross said of Jodie's killing: "I want to express my deepest sympathies to this girl's family and friends. Her death is a tragedy.
"I can reassure them and the whole community that we are doing everything possible to identify and bring to justice the person or persons responsible."
Urging potential witnesses to come forward, he added: "Your information could take a knife off the street or save a life."