ISLAMABAD, Pakistan (CNN) -- A radical cleric imprisoned for his role in a deadly Pakistan mosque siege has vowed to continue his campaign to impose hardline Islamic law in his first sermon since being released. Maulana Abdul Aziz gave his first sermon since being released from house arrest. Maulana Abdul Aziz was freed on Thursday -- nearly two years after siege at Islamabad's Red Mosque that left 90 people dead, including Aziz's son and brother. Addressing Friday prayers in the battle-scarred mosque, Aziz said he was willing to see more blood spilled for his cause. "My only son was killed for this great mission of Islam," he told a capacity crowd at the mosque. "If I had 100 sons, I would ask them to die for Islam."
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Cleric Maulana Abdul Aziz was freed from house arrest on Thursday
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Aziz was held for his role in 2007 mosque siege
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Cleric's spokesman says he supports the Taliban
Aziz was arrested after the Pakistani government laid siege to the mosque in July 2007 to crack down on its efforts to promote @placeholder-style sharia law.