A 15-year-old boy has been stabbed to death after a fight between two groups of youths.
Four teenagers have been arrested on suspicion of murdering the boy, who was attacked in a park in the South Yardley area of Birmingham last night. He died later from his injuries.
Two 16-year-olds, a 15-year-old and a 17-year-old are in custody, West Midlands Police said.
Detective Inspector Tom Chisholm, who is leading the investigation, said: "We are aware that there were groups of young people in the area, some of whom may have left the scene before the police arrived.
"There is some suggestion that this was a fight which has tragically gone too far. I would ask that people who were in the park or anyone else with information to contact us immediately."