A 15-year-old boy has died after being attacked in a residential street by a group of youths "armed with knives".
Police said Keon Lincoln was "set upon" at about 15:30 GMT on Thursday on Linwood Road, in Handsworth, Birmingham, and died later in hospital.
The attackers fled the scene in a car which crashed into a house a short distance away, added police, who said they had since seized the vehicle.
A 14-year-old boy has been arrested on suspicion of murder and is in custody.
The investigation is progressing "at pace", according to the West Midlands force, which detained the suspect on Friday morning.
Det Ch Insp Alastair Orencas, who is leading a murder inquiry, said Keon died "in the most violent of circumstances".
Witnesses who reported the carrying of knives to officers also said shots were heard.
Police confirmed Keon, who lived locally, was attacked with weapons but did not specify which sort.
The motive remained unknown said police, who urged those who could identify the attackers to contact the force.
"We are not sure of all the details at the moment, but we do know that Keon was set upon by this group and suffered a series of serious injuries," said Ch Supt Steve Graham, adding that five or six youths were believed to have been involved.
Police have not disclosed the nature of Keon's injuries. They say they are unable to say how he died before a post-mortem examination takes place.
Det Ch Insp Orencas said: "The death of Keon has shocked the whole community.
"This level of violence in broad daylight on a residential street is inconceivable, let alone the fact the target was a 15-year-old boy."
He said the family, who were being supported by specialist officers, "had the worst shock imaginable".
In a statement issued by police, the family said they were "devastated" by their loss, and remembered Keon as "fun-loving" and "full of life and love".
The tribute added: "He had an infectious laugh that lit up the room whenever he was in it."
Detectives are examining a white car they believe to be the getaway vehicle which crashed into a house on Wheeler Street.
CCTV footage has been seized and the area is cordoned off while investigations continue.
A resident of Linwood Road, who did not wish to be named, said she was shocked to hear someone had been killed.
She said: "We've lived here 45 years and I've never heard of anything like this.
"It's just shocking and really, really sad."
Keon died at Birmingham Children's Hospital.
Local Labour MP, Khalid Mahmood, described the death as "extremely tragic" and "a needless thing to have happened".
He said: "We must work with police as much as we can to stop this happening again."