LONDON , England ( CNN ) -- A habitually violent young man was convicted Wednesday of the murder of teenage actor Rob Knox , who had starred in the latest `` Harry Potter '' film . The father , brother and mother of Rob Knox pose together after the death of the young actor . Karl Bishop , 22 , attacked Knox and four friends with two kitchen knives outside a bar in Sidcup , south east London , last May . He stabbed them 10 times in less than two minutes , the Old Bailey court in central London heard . Knox , 18 , had rushed out of the bar after he heard that Bishop had threatened his younger brother Jamie but he ended up being stabbed five times , once in a main artery . He died in hospital later that night . Bystanders said Bishop 's face was `` screwed up in rage '' as he lashed out with the two knives , the Press Association reported . Days before the attack , the actor had finished filming on `` Harry Potter And The Half-Blood Prince , '' due for international release in July , in which he played the role of Marcus Belby . He was set to reprise the part in future `` Harry Potter '' films . Knox 's father Colin told mourners at his funeral , including co-star Rupert Grint , that his son had been `` living the dream , '' PA said . Prosecutor Brian Altman told the court that the young actor 's promising life was ended by a `` habitual knife carrier '' who believed stabbing people was an `` occupational hazard '' and had previous convictions for knife crime . Bishop is due to be sentenced on Thursday . Knife crime in Britain is a political hot topic due to a spate of recent killings of mainly young people in major cities . UK Prime Minister Gordon Brown has urged tougher sentences for those caught carrying knives . He told the Daily Telegraph last month : `` By carrying a knife you are not only endangering the lives of others , but you are more likely to be killed , or end up in jail . `` We need to change the way young people think about knives , we need families and communities working together ... to get this message across and help stamp out knife crime and get weapons off our streets . ''
Man convicted of murder of teenage actor who starred in new ` `` Harry Potter '' film . Rob Knox , 22 , attacked Rob Knox with 10 knives in southeast London 22 . Knife crime in London is political hot topic due to spate of recent killings .