In the 40-minute video released by al-Arabiya, an Arab news network, Shahzad, who last month pleaded guilty in the fizzled May 1 bombing attempt, said he hoped "the hearts of the Muslims will be pleased with this attack," the BBC reported.
"Eight years has passed by in Afghanistan and you will see that the Muslim war has just started," he says in the video said to have been made in Pakistan prior to the failed bombing.
"This attack on the United States will also be a revenge attack for all the mujahedin ... and the weak and oppressed Muslims, for example Baytullah Mehsud and Abu Musaab al-Zarqawi, and all the Muslims and Arabs that have been martyred."
ABC News reported an al-Arabiya producer said the tape was to be released after his death.
He is to be sentenced in October.
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