A murder investigation is underway after a man is stabbed during a fight in south London and later dies. Police are called to an incident in Thornton Heath, where a man sustains a stab wound. Following the attack, the injured man is taken to hospital but dies from his injuries. Officers investigate the circumstances surrounding the fight and the stabbing, and they treat the case as murder. Authorities arrest multiple suspects in connection with the incident, and three people are reported to be in custody. The investigation focuses on establishing what led to the fight, identifying those involved, and determining the sequence of events. Police appeal for information and may ask for any witnesses or anyone with relevant footage to come forward. The case remains under active investigation as detectives work to piece together details and confirm the identity of the victim and the circumstances of the attack.