The son of former Pakistani Prime Minister Benazir Bhutto has launched his political career on the fifth anniversary of his mother's death.
Bilawal Bhutto Zardari addressed thousands at a rally of Bhutto supporters in Garhi Khuda Baksh, the site of the family's mausoleum in Sindh Province.
Zardari, 24, is the third generation of his family to go into politics.
In his first major public speech, he said he would continue his family's fight against what he called "antidemocratic forces."
"We are faithful to Bhutto. If you kill one Bhutto, there will be a Bhutto in every house," he said.
Zardari, standing beside his father, President Asif Ali Zardari, also demanded that authorities find and convict those responsible for his mother's assassination.
Benazir Bhutto, who was twice elected Pakistan’s prime minister, was killed in a gun and suicide bomb attack on December 27, 2007, in Rawalpindi, the headquarters city of Pakistan’s military. No one has been convicted for the killing.
"I am the heir to the martyr [former President] Zulfiqar Ali Bhutto. I am the son of martyr Benazir Bhutto," he said. "I ask you why the killers of my mother, who have been arrested, are not being punished?"
Zardari, who is co-chairman of the Pakistan People’s Party (PPP), is ineligible to partake in national elections expected next year because he is too young -- the age limit being 25. But he is seen as a key asset for the ruling PPP in their campaign.
Zardari was made party chairman after his mother’s death but until now has played a background role as he completed his university studies overseas.
His father told the crowd it was now time for his son to settle in his native Pakistan.
"I feel proud today that the grandson of martyr Zulfiqar Ali Bhutto, my and Benazir Bhutto's son, and your worker is here with you," he said. "I want to tell you that with thanks to God, he has completed his studies, but the time has now come to complete his political training, to stay in Pakistan among its people and learn from them. He is to learn about Pakistan and its people. That's you."
Based on reporting by AFP and AP