Harry Potter actor stabbed to death protecting his younger brother

A teenage actor who appears in the next Harry Potter film was stabbed to death trying to protect his younger brother from a knifeman yesterday.

Robert Knox, 18, who acted alongside Daniel Radcliffe in Harry Potter and the Half-Blood Prince, became the 28th teenager killed in Britain this year, and the 10th in London to die from stab wounds.

Relatives said his role as Marcus Belby in the film, due for release in November, was set to launch his career as an actor.