A man was found guilty in a London court Wednesday of murdering teenage actor Rob Knox.

Knox, 18, who played the part of Marcus Belby in the soon to be released movie “Harry Potter and the Half-Blood Prince,” was stabbed five times outside of the Metro Bar in Sidcup, South East London.

The BBC reported Karl Bishop, 22, was convicted of murder and numerous other charges Wednesday and is to be sentenced Thursday.

Bishop reportedly was involved in an earlier brawl outside the pub, then returned to the bar armed with two kitchen knives and attacked bystanders. Knox was stabbed repeatedly as he attempted to protect his younger brother, Jamie.

“As a mother and parent, I can never forgive the person responsible for taking my son Robert’s life, or the devastation that has been caused by these actions,” Knox’s mother, Sally, said in a statement. “He was taken in the most cruel way possible.”

[Image via BBC]