The teenager stabbed to death at Hillingdon Civic Centre was attending a council-run knife awareness course for young offenders, police have revealed.

Hakim Sillah, 18, was killed after a fight broke out during the event in Uxbridge, west London, on Thursday.

The sixth-form student suffered a critical stab wound and died less than an hour after being airlifted to hospital. A 17-year-old boy was arrested and remains in custody.

Another 17-year-old, who was stabbed as he stepped in to break up the fight, was treated in hospital and has been discharged. Officers hailed his bravery as "amazing".

DCI Noel McHugh, who is leading the investigation, revealed yesterday that the boys were young offenders and the Met Police confirmed they were attending a course designed to tackle knife crime.

He said he was not aware of any security present at the event or if the teenagers were searched for weapons. The knife used in the attack has not yet been recovered.