Harry Potter actor Robert Knox has died after being stabbed in the early hours of yesterday morning.

The 18-year-old - who had just finished filming his supporting role as Ravenclaw student called Marcus Belby in Harry Potter and the Half-Blood Prince - was murdered outside the Metro Bar in Sidcup, London.

Knox was reportedly trying to protect his younger brother from the knife-man in a fight outside the bar, which also left three other people with serious injuries.

In a statement released yesterday, his parents said, “Rob was kind and thoughtful and would always help out others; he would always spend his last penny on other people instead of himself.

“The life and soul of the party, he was very outgoing, loved sports and would always strike up a conversation with people. He was respectful to others and adored by his family and friends.”

A 21-year-old has been arrested by police over the incident, which is said to have been caused by accusations of a stolen mobile phone.