Hampshire Police said officers were called shortly after 22:30 GMT to Park Road, where an “unknown group” had gained entry to the event. The injured boys were three 16-year-olds and two 17-year-olds. Parts of Park Road and nearby Valley Road were cordoned off as the investigation continued.
There is already a familiar gap between what is known and what people in the area are trying to fill in for themselves. Police have identified the broad shape of the event: a group got into the party, violence followed, and five boys ended up in hospital. They have not, at least in the account published by the BBC, explained the motive or said whether the victims were deliberately targeted.
Two witnesses told the BBC the trouble began after people came over a garden fence. One teenager described standing in the hallway near the exit and seeing someone he knew pull up his shirt and say he had been stabbed. He later saw him outside the house with someone compressing the wound. Another witness said “a big group of people started shouting and then a fight broke out” before adults told everyone to leave.
That is the kind of detail that makes the scene legible without quite making it coherent. A fence, shouting, a hallway near the exit, someone on the ground outside: enough to grasp how fast the night deteriorated, not enough to say why.
Detective Chief Inspector Elizabeth Pirie said officers were trying to trace all partygoers as well as people with relevant video footage. In an incident involving teenagers, that request does double duty. Video may help identify suspects, but it also tends to race through school and local social circles before the facts do.
The local institutions named so far suggest how tightly the shock is being felt. Barton Peveril Sixth Form College said two of the boys attacked were current students and that support was being offered. Thornden Secondary School said some former students had been injured and described the news as deeply upsetting for the school community.
Eastleigh MP Liz Jarvis urged people to stay calm and not share misinformation online. The Rev Duncan Hollands, vicar of Chandler’s Ford, called the attack awful, shocking and sad, and said the area was a peaceful place where “these sorts of things don't happen.”
Police, for their part, were still looking for the attackers.
Gabriel Fenech
Alex de Valletta
Marcus Azzopardi
Dua Mifsud