A Reebok TV ad should be banned because of its violent content, the Advertising Standards Authority (ASA) has ruled.
50 Cent was featured counting up the nine times he had been shot
The ad showed rapper 50 Cent counting the nine times he had been shot, then laughing as a voice asked who he planned to "massacre" next.
The ASA had 57 complaints from people claiming it glamorised gun culture, including Mothers Against Guns founder Lucy Cope, of Southwark, London.
The sports firm withdrew the ad from its I Am What I Am campaign last month.
Mrs Cope, whose son, Damian, was shot dead outside a nightclub in Holborn, north London, in 2002 aged 22, said she welcomed the ASA decision.
"As a victim and a campaigner, I thank them from the bottom of my heart. They don't realise it but they have saved lives," she said.
She called on Reebok bosses to meet members of Mothers Against Guns to discuss "how serious and how damaging that advertising was".
The ASA upheld the complaints about the glamorisation of gun culture, alongside others which said the advert made 50 Cent's background seem "cool".
It said the commercial breached the TV Advertising Standards Code by dealing "inappropriately" with violent aspects of 50 Cent's life.
Its overall affect was to imply the rapper's life was inspirational for the wrong reasons, with Reebok making no attempt to condemn the violence, the watchdog found.
It said the advert "endorsed his type of lifestyle and disregarded the unsavoury and perilous aspects of it by implying it was possible to survive being shot nine times".
Damian Cope was shot outside a London nightclub in 2002
Younger viewers were particularly likely to misread the message, the ASA said.
Reebok UK said the I Am What I Am series, approved by the Broadcast Advertising Clearance Centre, was intended to be a "positive and empowering celebration of the right of freedom of self-expression, individuality and authenticity".
It said the commercial did not condone violence or cruelty, adding that the question "Who do you plan to massacre next?" referred to the rapper's new album, The Massacre.
The firm said it had decided to pull the advert on 8 April after "a small number" of people "misinterpreted it and found it offensive".
Other celebrities featured in ads for the Reebok campaign include screen star Lucy Liu and sports stars Kelly Holmes, Allen Iverson and Iker Casillas.